DOW CHEMICAL COMPANY, PETITIONER V. UNITED STATES OF AMERICA

   No. 84-1259

   In The Supreme Court Of The United States

   October Term, 1985

   On Writ Of Certiorari To The United States Court Of Appeals For The
Sixth Circuit

   Brief For The United States

            TABLE OF CONTENTS
   Questions Presented
   Opinions below
   Statement
   Summary of argument
   Argument:
      I. Using standard, generally available photographic
         equipment to take aerial photographs of an outdoor
         manufacturing plant from navigable airspace does not
         violate the Fourth Amendment
         A. The Fourth Amendment does not generally prohibit
            government officials from observing areas exposed to
            their view from a place where they have a right to be
            1. There is no constitutional bar to viewing the
               "curtilage" from a vantage point to which the public
               has access
            2. The fact that the purpose of a police observation
               is to discover evidence does not automatically make
               the police conduct a "search" within the meaning of
               the Fourth Amendment
         B. Observation and ordinary photography from the air
            do not violate the Fourth Amendment
            1. There is no legitimate expectation that one can
               conduct outdoor activity free from the possibility
               of aerial observation
            2. There is no reasonable expectation that an
               outdoor facility will not be photographed from
               the air
            3. The fact that good quality aerial photographs
               are capable of revealing additional detail when
               enlarged and magnified does not give rise to a
               Fourth Amendment violation
            4. Society does not recognize a reasonable
               expectation of privacy in outdoor activity strong
               enough to outweigh the government interest in using
               aerial photography
            5. The existence of a trade secret in an outdoor
               area does not convert photography of that area into
               a Fourth Amendment violation
      II. The use of aerial photography does not exceed
          the scope of EPA's statutory authority
   Conclusion

                            Opinions Below

   The opinion of the court of appeals (Pet. App. A1-A14) is reported
at 749 F.2d 307.  The opinion of the district court (Pet. App. B1-B45)
is reported at 536 F. Supp. 1355.

                             Jurisdiction

   The judgment of the court of appeals was entered on November 9,
1984.  The petition for a writ of certiorari was filed on February 7,
1985, and was granted on June 10, 1985.  The jurisdiction of this
Court is invoked under 28 U.S.C. 1254(1).

                          Questions Presented

   1. Whether the Environmental Protection Agency (EPA) violated the
Fourth Amendment by contracting with a private company to take aerial
photographs of a chemical plant from public navigable airspace with
standard aerial camera equipment.

   2. Whether the procurement of aerial photographs of chemical plants
by EPA exceeds its statutory authority.

                               Statement

   1. Petitioner owns and operates a large chemical manufacturing
facility in Midland, Michigan, which occupies approximately 2,000
acres in an area that is characterized by light to medium development.
 Petitioner's plant is located near an airport, and commercial
aircraft frequently pass over and near the property.  At the Midland
location, petitioner owns and operates two power plants known as the
South Side Power Plant and the West Side Power Plant.  Pet. App. A9,
B2.

   In late 1977 and early 1978, enforcement officials of the
Environmental Protection Agency (EPA) were gathering information
concerning emissions from these power plants with the intention of
bringing an enforcement action under the Clean Air Act, 42 U.S.C. 7401
et seq.  EPA officials made an on-site inspection of the power plants
in September 1977, but petitioner refused to accede to a subsequent
request for a second inspection.  Pet. App. A2.  Thereafter, EPA
enforcement officials decided to obtain aerial photographs of
petitioner's Midland power plants in order to attempt to visualize the
emissions from the stacks, to see the layout of the facilities, and to
look at the effects of emissions on surrounding vegetation (J.A. A30).
 They contacted EPA'S Environmental Monitoring and Surveillance
Laboratory (EMSL) in Las Vegas, Nevada, and ordered the photographs.
EMSL, in turn, contracted with Abrams Aerial Survey Corporation
(Abrams), a local aerial photography business, to take photographs of
the Dow plant.  Pet. App. A2.

   On February 7, 1978, an Abrams employee flew over petitioner's
facility and took photographs.  These photographs were taken when the
airplane was flying at altitudes of 12,000, 3,000 and 1,200 feet.  The
camera used was a Wild RC-10 aerial mapping camera with a six-inch
lens and a focal length of 150 millimeters.  The photographs taken at
1,200 feet show the plant at a scale of 1 inch to 200 feet.  Abrams
sent the undeveloped film to EMSL by courier service.  There, EPA
technicians developed the film and made several prints and
enlargements of the power plants.  The most detailed of the
enlargements was a 2x enlargement of one of the photographs taken at
the lowest altitude, resulting in a scale of 100 feet to the inch.
See J.A. A42.  The film and enlargements were then sent to EPA'S
Region V enforcement office in Chicago, Illinois.  Pet App. A3.

   2. On March 15, 1978, petitioner brought an action for injunctive
and declaratory relief against the United States and EPA.  It alleged
that aerial photography of its Midland plant violated its Fourth
Amendment rights and deprived it of trade secret property interests in
violation of the Fifth Amendment.  Petitioner sought to obtain the
photographs and to enjoin EPA'S future use of aerial photography of
the Midland plant.  The court entered a temporary restraining order
enjoining EPA from disseminating, releasing, copying, or duplicating
the photographs or releasing information derived therefrom.
Subsequently, the court entered a preliminary injunction, and the
negatives and prints made by EPA were deposited, under seal, in the
district court.  /1/

   On April 19, 1982, the district court granted petitioner's motion
for partial summary judgment and ruled that the aerial photography
violated petitioner's Fourth Amendment rights.  /2/ First, the court
ruled that because EPA admittedly was engaged in a "quest for
evidence" (Pet. App. B6), the warrantless aerial photography was an
unlawful administrative search.  Id. at B5-B17.  In the alternative,
the district court analyzed the case under Katz v. United States, 389
U.S. 347 (1967), to determine whether petitioner had a reasonable
expectation of privacy upon which EPA had infringed.  It found that
because petitioner had designed its plant so that some outdoor
portions of the facility were not visible to a person standing on the
ground at the plant boundary, it had an expectation of privacy in
these outdoor facilities.  The court also found that the aerial
photography was a form of "visually enhanced surveillance" subject to
special restriction because "EPA could later analyze (the photographs)
under enlarged and magnified conditions" (Pet. App. B27).  See id. at
B17-B32.  Finally, the district court ruled that the "open fields"
doctrine did not apply when a property owner's expectation of privacy
was objectively reasonable.  In this regard, it relied (Pet. App.
B32-B-38) on the panel decision in United States v. Oliver, 657 F.2d
85 (1981), which was subsequently rejected both by the en banc court
of appeals, 686 F.2d 356 (6th Cir. 1982), and by this Court, Oliver v.
United States, No. 82-15 (Apr. 17, 1984).

   The district court also ruled that Section 114 of the Clean Air
Act, 42 U.S.C. 7414, which grants EPA inspectors the "right of entry
to, upon, or through any premises" in certain circumstances, impliedly
excluded EPA from using other techniques, such as aerial surveillance
or photography, as an investigative tool.  The court ruled that
Congress intended that "only land-based inspections be utilized" (Pet.
App. B44).  Hence, it held that the overflights exceeded EPA's
statutory authority.  Id. at B39-B44.  Accordingly, the court entered
a permanent injunction against use of the photographs and against any
future aerial surveillance and photography of petitioner's facility
(id. at B45).

   3. The court of appeals reversed (Pet. App. A1-A14).  Looking to
whether petitioner had a reasonable expectation of privacy in the
areas in question, the court concluded that no reasonable expectation
of privacy was invaded in photographing from the air the "outdoor
spaces of a chemical plant" (id. at A13).  The court reasoned that
petitioner had exhibited no actual expectation of privacy from aerial
observation of its large industrial plant (id. at A7-A8).  Even if it
had such an expectation, moreover, the court explained that society
would not deem it to be reasonable (id. at A9):

      When the entity observed is a multi-building complex, and the
      area observed is the outside of these buildings and the spaces
      in between the buildings, and when the complex is near an
      airport and within the pattern of planes landing and taking off,
      it is difficult to see how a reasonable person would have
      privacy expectations in the outside of the buildings and the
      spaces between the buildings.

   The court distinguished the open-air facilities involved here from
petitioner's offices and enclosed facilities, where the Court
recognized the existence of "strong expectations of privacy" (id. at
A11).

   The court of appeals also reversed the district court's ruling that
the flights were unlawful because EPA was not authorized by statute to
use aerial photography as an investigative technique.  It ruled that
Congress's delegation under the Clean Air Act of general investigative
authority to EPA was sufficient statutory authority to conduct aerial
observation that satisfied the Fourth Amendment.  Pet App. A13-A14.

                          Summary Of Argument

                                  I.

   A. It is a truism of Fourth Amendment law that a government
official is not "precluded from observing as an officer what would be
entirely visible to him as a private citizen." Texas v. Brown, 460
U.S. 730, 740 (1983) (plurality opinion).  Several decisions of this
Court make clear that a prohibition on entry into a particular area is
not equivalent to a prohibition on viewing that area from some other
place where the officer may be without violating the party's property
or privacy rights.  Therefore, whether petitioner's outdoor facility
is termed an "open field" or "curtilage" or something else, there is
no constitutional bar to government agents' viewing it from a vantage
point to which the public has access.  Moreover, there is no
constitutional requirement that the government have any patricular
quantum of suspicion in so viewing private property, even if it is
looking for something in particular and therefore in that sense
conducting a "search".  If a government attempt to obtain information
does not infringe a legitimate expectation of privacy, it plainly is
not an "unreasonable" search, and there is no need to establish a
basis for suspicion in order to satisfy the Fourth Amendment.  In such
circumstances, the fact that the government deliberately observes a
person's visible property does not mean that it has conducted a
"search" within the meaning of the Fourth Amendment.

   B. The photographs involved here were taken from a plane flying in
navigable airspace, above the minimum altitude, and thus in a region
that has been designated by Congress as the equivalent of a public
aerial highway.  There is no legal or physical barrier to prevent
anyone flying in navigable airspace from looking down into
petitioner's outdoor facility, or indeed the curtilage of a home,
while flying in one of the more than 260,000 aircraft registered in
the United States.  Thus, there is no legitimate expectation that
outdoor activity will not be observed from the air.  To the extent
that this possibility of aerial observation constitutes a loss of
privacy, it is lost to the public at large.  No legitimate privacy
interest would be served by imposing upon the government a special
limitation on aerial observation;  in Fourth Amendment terms, such
observation by the government does not intrude into a legitimate
subjective expectation of privacy.

   The same principles apply when a photograph is taken from an
airplane flying overhead.  The photographs here were taken by a
private contractor with standard, commercially available camera
equipment.  Any member of the public could have taken, or contracted
for, such pictures.  Moreover, government agencies regularly and
routinely engage in aerial photography for mapping and other
noninvestigative purposes.  Thus, petitioner could have no legitimate
expectation that its plant would not be photographed from the air.  In
the absence of an intrusion into such a legitimate expectation of
privacy, there is no constitutional probhibition on the use of
technology to enhance human senses.  See, e.g., United States v.
Knotts, 460 U.S. 276, 282 (1983) (beeper);  Lopez v. United States,
373 U.S. 427, 439 (1963) (sound recording);  United States v. Lee, 274
U.S. 559, 563 (1927) (searchlight, binoculars).

   Petitioner contends that the level of detail potentially capable of
being revealed by enlargement and magnification of the photographs
taken for EPA establishes a Fourth Amendment violation, but this issue
is not genuinely presented in this case.  The enlargements of which
petitioner complains were made by petitioner itself -- of a portion of
the plant and at a level of detail unnecessary to EPA's investigation.
 But the Fourth Amendment inquiry must focus on any privacy intrusion
actually committed by the government, not on the potential intrusion
that theoretically could result if the government were to take further
steps.  The fact that the government could obtain certain information
by technologically enhancing the photographs it has taken should not
be controlling if the government does not take such action.  In any
event, petitioner can have no legitimate expectation of privacy in
details of its plant that can be revealed by ordinary enlargement and
magnification of the photographs.  These techniques are available to
the public, and the Fourth Amendment does not prohibit the government
from using them as well.  Moreover, petitioner offers no basis for
determining when a particular level of detail has become
constitutionally offensive other than the subjective desires of the
complaining party.

   Even if there were a subjective expectation of privacy in an
outdoor facility, it would not be one that society recognizes as
reasonable.  Outdoor areas ordinarily "do not provide the setting for
those intimate activities that the (Fourth) Amendment is intended to
shelter from the government interference or surveillance." Oliver v.
United States, No. 82-15 (Apr. 17, 1984), slip op. 7.  Whatever
minimal privacy interest one could imagine as being infringed by the
possibility of aerial observation of outdoor activity cannot outweigh
the important public interests served by the use of that technique to
assist government regulation and law enforcement.  This is
particularly so when the area in question is an industrial facility,
rather than the curtilage of a home.

   Even if, as petitioner contends, the configuration of pipes or
other details of its outdoor plant may constitute a "trade secret,"
that fact would have no bearing on the Fourth Amendment question at
issue here.  Trade secret laws are designed to protect against unfair
competition by preventing the unauthorized disclosure or use of a
trade secret.  These laws do not purport to establish any privacy
interest that would be infringed by observation, and they provide no
guidance for the constitutional inquiry.  For example, even if aerial
photographs were regarded as an improper means of obtaining a trade
secret for purposes of unfair competition law, as disclosure of
confidential information by a former employee would be, that would not
mean that the method violates the Fourth Amendment.  Moreover, the
government has no interest in building a chemical plant to compete
with petitioner or otherwise using the trade secret;  therefore, its
mere possession of particular information would not even violate the
trade secret laws and ought to cause petitioner no concern.  Indeed,
numerous statutes contemplate that companies will turn over their
trade secrets to the government in the course of normal business.

                                 II.

   It is clear that the overflight here was not invalid for lack of
statutory authority.  When Congress invests a government agency with
law enforcement and investigatory authority, it is naturally and
properly assumed that the agency is entitled to use any methods of
investigation that could lawfully be employed by private
investigators, even if not specifically enumerated in the statute.
Nothing in the Clean Air Act gives any reason to doubt the correctness
of this assumption.  Plainly, the expansion of EPA's powers to
authorize it to enter and inspect private premises in conducting its
inquiries carries no negative implication prohibiting other, less
intrusive forms of investigation.

                               ARGUMENT

 I. USING STANDARD, GENERALLY AVAILABLE PHOTOGRAPHIC EQUIPMENT TO TAKE
AERIAL PHOTOGRAPHS OF AN OUTDOOR MANUFACTURING PLANT FROM NAVIGABLE
AIRSPACE DOES NOT VIOLATE THE FOURTH AMENDMENT

   Petitioner contends that the EPA violated the Fourth Amendment when
it engaged a private concern to take aerial photographs of its outdoor
chemical plant.  Petitioner appears to advance several alternative,
albeit related, contentions.  First, because it has taken steps to
exclude the public from entry onto the plant grounds, petitioner
asserts that the plant is not an "open field" and hence that it is
protected from observation by agents of the government in the absence
of probable cause and a warrant (Br. 19-24).  In any event, petitioner
contends that the aerial observation that took place here violated the
Fourth Amendment.  Petitioner appears to contend that it is unlawful
to view its facility from the air because it has taken extensive
measures to prevent observation from the ground (see id. at 7-9,
16-17, 21), and it particularly objects to the use of aerial
photography, arguing that the Fourth Amendment prohibits anything
other than unaided "naked eye" viewing (id. at 24-30).  Finally,
petitioner contends that the capacity of the photographs to reveal
detail through enlargement and magnification demonstrates a Fourth
Amendment violation (id. at 31-41).

   The court of appeals correctly rejected these contentions.  Even if
one accepts petitioner's argument that the plant is not like an "open
field" insofar as the public is denied access, this does not mean that
the plant may not be viewed by the public (or the government) from a
vantage point to which it undisputedly does have access.  Put another
way, the fact that an area is protected from physical entry does not
mean that the law provides an additional barrier to observation from
outside the property where none exists in fact.  And the Fourth
Amendment does not prevent the use of a camera to record an otherwise
lawful visual observation.

 A. The Fourth Amendment Does Not Generally Prohibit Government
Officials From Observing Areas Exposed To Their View From A Place
Where They Have A Right To Be

 1. There Is No Constitutional Bar To Viewing The "Curtilage" From A
Vantage Point To Which The Public Has Access

   In Oliver v. United States, No. 82-15 (Apr. 17, 1984), the Court
reaffirmed the "open fields" doctrine, which was first recognized in
Hester v. United States, 265 U.S. 57 (1924).  The Court held that the
Fourth Amendment is not violated by a government entry onto open
fields even though the entry is an uninvited trespassory intrusion
onto private property.  The Court first noted (Oliver, slip op. 4-5)
that open fields beyond the curtilage of a dwelling are not properly
classified among the "persons, houses, papers, and effects" to which
the protections of the Fourth Amendment apply.  It then explained that
the same result would also be independently reached under the
"expectation of privacy" analysis of Katz v. United States, 389 U.S.
347 (1967).  First, "open fields do not provide the setting for those
intimate activities that the (Fourth) Amendment is intended to shelter
from government interference or surveillance" (Oliver, slip op. 7).
In addition, despite his ownership interest and manifestations of that
interest such as fences or no trespassing signs, a landowner has no
reasonable expectation of privacy in his open fields because "as a
practical matter these lands usually are accessible to the public and
the police in ways that a home, office or commerical structure would
not be" (ibid).  The "open fields" doctrine thus is an illustration of
the more general principle that "there is no reason (why a policeman
or other government official) should be precluded from observing as an
officer what would be entirely visible to him as a private citizen."
Texas v. Brown, 460 U.S. 730, 740 (1983) (plurality opinion).  See
also Maryland v. Macon, No. 84-778 (June 17, 1985), slip op. 5;
Marshall v. Barlow's, Inc., 436 U.S. 307, 315 (1978);  Air Pollution
Variance Board v. Western Alfalfa Corp., 416 U.S. 861, 865 (1974).

   In Oliver, the Court distinguished "open fields" from the common
law concept of "curtilage," described as "the land immediately
surrounding and associated with the home" (id. at 8).  While the Court
expressly did not consider the scope of Fourth Amendment protection of
the curtilage as opposed to the home (id. at 9 n.11), it suggested
that areas considered part of the curtilage would have greater
constitutional protection than open fields.  Petitioner seizes upon
this distinction to support its challenge to EPA'S aerial viewing of
its outdoor plant.  Petitioner contends that the outdoor portions of
its plant are not "open fields," but rather are a "business curtilage"
(Br. 20) that cannot constitutionally be viewed from the air.  This
contention misperceives the nature of the issue in Oliver and of the
Fourth Amendment protection of privacy in the curtilage.  /3/

   It was never disputed in Oliver that the police were entitled to
look into the landowner's property and see whatever they could see
while standing on public property.  The focus of the litigation in
Oliver was over the right of police to enter the property;  regardless
of the outcome of the case there would have been no bar to observation
of the private property from outside, whether from the ground or the
air (see slip op. 7 n.9).  The same assumptions that underlay the
Court's deliberations in Oliver apply to the curtilage.  The fact that
the Fourth Amendment may protect against entry in the absence of
probable cause or a warrant does not mean that the Constitution erects
a barrier to visual observation from areas open to the public.  See,
e.g., Texas v. Brown, supra (looking into an automobile);  United
States v. Santana, 427 U.S. 38 (1976) (observing individual in doorway
of her home);  United States v. Lee, 274 U.S. 559 (1927) (looking onto
a boat deck).  This conclusion is particularly apt in the case of the
common law concept of curtilage, which originated in the course of
defining what intrusions into the area of the home would constitute a
burglary (see 4 W. Blackstone, Commentaries on the Laws of England ch.
16, at 225 (Univ. of Chicago Press ed. 1979));  the notion of
curtilage focuses on physical entry, not freedom from observation.
Thus, petitioner's assertion here that its plant is not an "open
field", but rather something akin to curtilage that is entitled to
Fourth Amendment protection, does not address the question presented
of the lawfulness of the observation of the plant from public
navigable airspace.

   This Court has never suggested that the Fourth Amendment prohibits
government officials from observing the curtilage;  indeed, a long
line of decisions plainly demonstrates that the Court has always
assumed that such observation is lawful.  In Hester, for example, the
police officers who entered the open field were able to observe the
defendant in possession of contraband just outside the doorstep of his
house.  265 U.S. at 58.  Once the Court determined that the trespass
did not violate the Fourth Amendment, it did not doubt that the
officers lawfully could observe the defendant's activities from their
vantage point in the open field, although those activities almost
surely took place within the curtilage.  Similarly, in United States
v. Karo, No. 83-850 (July 3, 1984), and United States v. Knotts, 460
U.S. 276 (1983), the Court considered the Fourth Amendment
implications of police monitoring of a "beeper" transmitting signals
from in or near a privately owned building.  The Court found
manifestly unobjectionable the use of a beeper to obtain information
available from visual surveillance, even if that surveillance extended
up to the door of a residence (see Karo, slip op. 7-9;  460 U.S. at
281-282, 285).  The only Fourth Amendment problem arose from the use
of the beeper "to obtain information that it could not have obtained
by observation from outside the curtilage of the house" (Karo, slip
op. 9).  In sum, the fact that government officials may lack authority
in a given situation to enter the curtilage of a residence does not
prevent them from standing outside the curtilage and looking inside to
observe what is exposed to their view from that vantage point.  See
also Fullbright v. United States, 392 F.2d 432, 434-435 (10th Cir.),
cert. denied, 393 U.S. 830 (1968).

 2. The Fact That The Purpose Of A Police Observation Is To Discover
Evidence Does Not Automatically Make The Police Conduct A "Search"
Within the Meaning Of The Fourth Amendment

   Contrary to petitioner's contention (Br. 27-30), the fact that
government officials are looking for something, and hence can be
colloquially described as conducting a "search", does not mean that
their activity is violative of the Fourth Amendment if done in the
absence of probable cause and a warrant.  In Fourth Amendment terms,
"(a) 'search' occurs 'when an expectation of privacy that society is
prepared to consider reasonable is infringed.'" United States v. Karo,
slip op. 6 (quoting United States v. Jacobsen, No. 82-1167 (April 2,
1984), slip op. 3).  This is because in those situations where there
is no intrusion into a legitimate expectation of privacy, the
investigative activity is presumptively reasonable even in the absence
of any suspicion at all, and hence the Fourth Amendment's protection
against "unreasonable" searches does not even come into play.

   Obviously, when police scour the streets looking for a suspect or
wait by the side of the highway looking for a particular car, they are
conducting a "search", but their activity raises no Fourth Amendment
question.  Similarly, the Court has held that police may enter and
inspect an open field (Oliver), have a dog sniff luggage (United
States v. Place, 462 U.S. 696, 706-707 (1983)), and field test for
cocaine (United States v. Jacobsen, supra) without any particularized
suspicion of criminal activity.  These measures do not implicate
sufficiently weighty privacy interests to be deemed unreasonable in
the absence of such suspicion (see Oliver, slip op. 5);  hence, use of
these measures does not invoke Fourth Amendment scrutiny of the
justification for the search.  For this reason, such measures are not
"searches" within the meaning of the Fourth Amendment, although they
plainly involve "searches" in the ordinary sense of looking for
something.  See Oliver, slip op. 11;  Place, 462 U.S. at 707;
Jacobsen, slip op. 10, 12.  By the same token, the fact that
government officials who peer into exposed curtilage may be
"searching" for something does not mean that they are conducting a
"search" within the meaning of the Fourth Amendment -- i.e., that
their activity is unreasonable in the absence of a particular degree
of suspicion.  /4/

 B. Observation And Ordinary Photography From The Air Do Not Violate
The Fourth Amendment

   Petitioner's primary contention is that, even if ground level
observation of activities and structures on the curtilage from a point
outside the curtilage would be permitted, the use of airplanes, and
particularly aerial photography, to observe its chemical plant is
unconstitutional.  Petitioner's assertion that these methods of
observation invade its legitimate expectation of privacy must be
assessed by reference to the two-part inquiry first set forth by
Justice Harlan in his concurring opinion in Katz v. United States, 389
U.S. at 361 (1967), and subsequently embraced by the full Court.  See,
e.g., United States v. Knotts, 460 U.S. at 280-281;  Smith v.
Maryland, 442 U.S. 735 (1979).  Under this test, an individual has a
legitimate expectation of privacy subject to constitutitional
protection in a particular area or activity if he has exhibited a
subjective expectation of privacy and if that expectation is one that
society is prepared to recognize as reasonable.

   The first part of the test recognizes that there are situations in
which even essentially private activities that ordinarily warrant
Fourth Amendment protection nonetheless can be devoid of any
legitimate expectation of privacy because an individual engages in
those activities in a manner that is not calculated to shield them
from the public.  If these otherwise private matters are exposed to
the public, then they are equally exposed to government officials.
Thus, an individual lacks a legitimate expectation of privacy in a
private conversation that is loud enough to be overheard by passersby
(Katz, 389 U.S. at 361 (Harlan, J., concurring)), in private papers
that he leaves exposed on a park bench, or in reading material that he
sells to the public (Maryland v. Macon, supra).  The second part of
the test recognizes that the mere fact that an individual has taken
steps to protect certain activities from observation by the public
does not automatically mean that they are protected by the Fourth
Amendment.  Some activities and areas are sufficiently removed from
the intimate private activities whose protection is at the core of the
Fourth Amendment that the government's interest in effectively
conducting its business outweighs the limited privacy interest
involved.  For example, even if a landowner takes steps to exclude the
public from his marijuana fields, the Fourth Amendment does not
prevent police from entering to investigate the illegal enterprise
(Oliver, slip op. 13).  /5/

 1. There Is No Legitimate Expectation That One Can Conduct Outdoor
Activity Free From The Possibility Of Aerial Observation

   In today's society, there can be no reasonable subjective
expectation that outdoor activity will be free from overflights by
aircraft and the possibility of observation from such aircraft.  Since
1926, there has been a public right of travel in airspace above
prescribed minimum altitudes of flight.  See Air Commerce Act of 1926,
ch. 344, Section 10, 44 Stat. 574.  /6/ By regulation, the minimum
altitude for fixed wing aircraft has been set at 1,000 feet in
congested areas and 500 feet in uncongested areas.  14 C.F.R. 91.79.
/7/ In addition to commercial air carriers, this public highway
through the air is used by more than 260,000 aircraft registered in
the United States, which log more than 36 million flight hours per
year.  FAA, U.S. Dep't of Transportation, No. AMS-420, Census of U.S.
Civil Aircraft 4, 46, 54 (Dec. 31, 1983).  Airplanes and helicopters
flying at relatively low altitudes are used routinely to perform such
diverse functions as providing traffic reports, crop dusting, shooting
film for news programs, sightseeing, and getting from one place to
another.  There is nothing to prevent the 718,000 active pilots (id.
at 46) or their passengers on these planes from looking down and
abserving what they can see on the ground below from altitudes as low
as 1,000 feet.  /8/

   Indeed, the litigation in Oliver was premised on the assumption by
the parties and the Court that "the public and police lawfully may
survey lands from the air." Slip op. 7 (footnote omitted).  The Court
relied on the fact that repudiation of the "open fields" doctrine
would have little practical effect because law enforcement officials
could resort to aerial surveillance (id. at 7 n.9).  Even the
dissenting opinion in the en banc court of appeals in Oliver shared
this premise, although it disagreed with this Court's ultimate
conclusion that an entry into open fields was permitted:  "Oliver did
not have a reasonable expectation of privacy from planes or
helicopters flying overhead.  Thus, the officers could have lawfully
used airplanes or helicopters to observe the marijuana from the air."
686 F.2d at 372 (Keith, J., dissenting).  /9/

   Establishment of a rule making it a Fourth Amendment violation to
look down into the curtilage from a passing airplane would lead to
strange results.  Government officials would be forced to avert their
eyes from the ground during flight even as other members of the public
looked down.  Moreover, because aircraft may come upon structures
suddently and, in any event, it is difficult to distinguish between
the curtilage and open fields, the practical effect of such a rule
would be to prevent government officials from observing even open
fields from the air -- an action that everyone agrees is lawful.  See
United States v. Bassford, 601 F. Supp. 1324, 1331-1332 (D. Me. 1985).
 Indeed, petitioner itself at times appears to concede that aerial
observation with the naked eye does not implicate the Fourth Amendment
(see Br. 25, 37).  In short, Congress's establishment of a public
right to freedom of transit in navigable airspace necessarily
constitutes a decision in favor of the social and economic advantages
of relatively unrestrained aviation at the expense of the loss of some
degree of privacy from airborne observation.  That privacy has been
lost to the public, and it cannot be recaptured by reading the Fourth
Amendment to impose special limitations upon the viewing ability of
government officials.

 2. There Is No Reasonable Expectation That An Outdoor Facility Will
Not Be Photographed From The Air

   Petitioner correctly notes that aerial photography allows more to
be seen than mere observation from the air by the unaided human eye.
The creation of a permanent record may make it easier for the observer
to comprehend fully what is exposed to his view.  Moreover, it is
usually possible to enlarge a photograph, thus exposing more detail
than could be seen with the naked eye from the same vantage point.
/10/ It does not follow, however, that an individual has a legitimate
expectation that his outdoor activity or facility will be free from
the possibility of being photographed from a plane flying overhead.

   As this Court's own decisions reflect (see Nebraska v. Wyoming, 325
U.S. 589, 668 (1945);  Kansas v. Missouri, 322 U.S. 213, 220 (1944)),
aerial photography has been practiced on a regular basis since the
early days of aviation.  See generally Wick, Aerial Photography of
Real Property and Its Admissibility into Evidence, 1 Northrup U.L.J.
113 (1979).  Aerial photography is frequently employed by both
governments and private persons for a variety of useful purposes.
/11/ In contrast to wiretapping (see Berger v. New York, 388 U.S. 41,
45-49 (1967)), there is no history of federal or state laws generally
restricting aerial photography.  Congress has acted to prohibit the
use of such photography only in very limited circumstances (see 18
U.S.C. 796 (military installations);  42 U.S.C. 2278(b) (designated
national security-related nuclear facilities)) and otherwise has
allowed its widespread use.  Indeed, the common use of this technique
is evidenced in this case by the fact that the EPA did not need to go
to great lengths to obtain the photographs.  It simply hired a local
contractor whose business was aerial photography.

   The record in this case shows that the government routinely engages
in aerial photography for diverse purposes having nothing at all to do
with investigating criminal activity or discovering regulatory
violations.  See, e.g. Affidavit of G. LaRoche, Nuclear Regulatory
Commission (site evaluation and emergency response planning for
nuclear power plants);  Affidavit of J. Jarman, United States Forest
Service (watershed, flood plain, and resource survey);  Affidavit of
R. McArdle, Department of Agriculture (wetlands and soil
conversation).  See also United States v. Tull, No. 84-1766 (4th Cir.
July 30, 1985), slip op. 14, n.5.  The same is true of state
governments.  Indeed, the record shows that petitioner's Midland plant
was photographed from the air by the Michigan Department of Natural
Resources pursuant to its regular regulatory functions (J.A. A54).
Thus, petitioner's outdoor plant is exposed to observation and
photography from the air, and such photography is known to be
relatively common.  In these circumstances, it cannot reasonably be
asserted that petitioner had any genuine subjective expectation of
privacy from aerial photography.

   Notwithstanding the fact that it could not reasonably entertain a
subjective expectation of privacy from aerial photography, petitioner
argues (Br. 16, 25, 30, 31, 37-39) that the use of technology such as
a camera to enhance the vision of the naked eye is so inherently
intrusive that it must be deemed violative of the Fourth Amendment.
This broad proposition is clearly without support in established
Fourth Amendment jurisprudence.  In United States v. Knotts, 460 U.S.
at 282, the Court observed that "(n)othing in the Fourth Amendment
prohibited the police from augmenting the sensory faculties bestowed
upon them at birth with such enhancement as science and technology
afforded them in this case" (a beeper).  While this statement does not
mean that there are no constitutional limits on the use of
technological developments to aid the police, it reflects the Court's
consistent recognition that the Fourth Amendment does not restrict
government investigators to observation by the unaided human senses.
/12/ A long line of authority has recognized the use of relatively
common devices to enhance vision, hearing, smell, and memory.

   The Court has not specifically confronted the question whether
photography of an area that a government official may lawfully view
with the naked eye violates the Fourth Amendment, but its decisions on
related questions leave little doubt that it does not.  In United
States, v. Lee, supra, the Court ruled that there was no
constitutional bar to the use of a searchlight to illuminate a dark
area into which officers could not otherwise see.  The Court
analogized the use of the searchlight to the use of binoculars, which
it regarded as so plainly constitutional that it did not warrant
discussion.  274 U.S. at 563.  See also On Lee v. United States, 343
U.S. 747, 754 (1952).  The mere fact that human vision is enhanced in
a way that allows an observer to see more detail does not create a
constitutional violation.  By the same token, the mere fact that the
camera creates a permanent record of a view that is only transitory to
the naked eye does not prohibit its use.  In Lopez v. United States,
373 U.S. 427, 439 (1963), the Court recognized that an undercover
police officer may surreptitiously record a private conversation;
indeed, he may even carry a transmitter to broadcast the conversation
to other police officers.  See United States v. Caceres, 440 U.S. 741,
750-751 (1979);  United States v. White, 401 U.S. 745 (1971).  As long
as he is listening to the conversation lawfully, there is no bar to
recording it for permanent use.  Against this background, there is
little basis for the contention that the police or other government
officials are constitutionally prohibited from photographing what they
can lawfully observe with the naked eye (or through eyeglasses).  See
also United States v. Crews, 445 U.S. 463, 474-475 (1980) (plurality
opinion).

   The courts of appeals have recognized that government officials are
entitled to take photographs or make other permanent records of things
that they lawfully observe.  In United States v. Allen, 675 F.2d 1373,
1379-1381 (9th Cir. 1980), cert. denied, 454 U.S. 833 (1981), the
court upheld the admissibility of photographs taken from a helicopter
with a telephoto lens.  See also United States v. Hensel, 509 F. Supp.
1376, 1379 (D. Me. 1981), aff'd, 699 F.2d 18, 41 (1st Cir.), cert.
denied, 461 U.S. 958 (1983) (aerial photographs);  United States v.
Espinoza, 641 F.2d 153, 167 (4th Cir. 1981) (photographs on ground);
United States v. Thomas, 613 F.2d 787, 793 (10th Cir. 1980)
(photocopies).  And the courts have repeatedly upheld the use of
vision enlarging aids such as binoculars.  See, e.g., United States v.
Hensel, 699 F.2d at 41;  United States v. Dubrofsky, 581 F.2d 208, 211
(9th Cir. 1978);  United States v. Minton, 488 F.2d 37, 38 (4th Cir.
1973), cert. denied, 416 U.S. 936 (1974);  Fullbright v. United
States, supra.  /13/

 3. The Fact That Good Quality Aerial Photographs Are Capable Of
Revealing Additional Detail When Enlarged And Magnified Does Not Give
Rise To A Fourth Amendment Violation

   Perhaps recognizing the difficulty in contending that it has a
legitimate expectation of privacy from aerial photography generally,
petitioner devotes part of its brief (at 35-41) to what appears to be
an extremely case-specific contention, namely, that the particular
photographs taken here -- because of the degree of detail of
petitioner's chemical plant capable of being revealed by enlargements
of those photographs viewed under magnification -- were so intrusive
that they should be held to violate the Fourth Amendment.  This
position is somewhat unfocused, but it appears to suggest an
unacceptable regime in which the dispositive factor would be the
degree to which an individual subjectively desires to be free from
aerial observation -- a standard that would make it all but impossible
for government officials to have known in advance whether their
conduct comports with the Fourth Amendment.  Before turning to this
contention, however, it is important to emphasize that this case does
not genuinely present the case-specific question addressed by
petitioner;  the intrusion that petitioner asserts would be
unconstitutional is a hypothetical one that was not actually
established by any actions taken by the government in this case.

   a. The Fourth Amendment issue in this case comes to the Court in a
most peculiar context.  There has been no attempt by the government to
introduce any evidence gleaned from the overflight against petitioner
in any judicial or other proceeding, and thus there is no specific
evidence that is sought to be suppressed.  Rather, it is petitioner
that commenced this litigation, seeking to enjoin the government from
any use of the information obtained from the aerial photography.
Petitioner's arguments accordingly have been addressed to the entire
array of photographs taken and what they theoretically are capable of
revealing through the further application of enlargement and
magnification technology.  The particular level of detail about which
petitioner expresses principal concern in this Court (see Br. 12,
37-39;  Sealed Joint Appendix, Photographs 4 & 5) is found in
enlargements created not by the government, but by petitioner itself;
these enlargements have never been in the government's possession
except in a theoretical sense.  /14/

   There is no reason to suppose that the government would ever have
made enlargements like those made by petitioner, for they do not
relate to any matter in which the government has expressed an
interest.  The government was investigating the two power plants at
petitioner's Midland facility, and EPA officials did make modest 2x
enlargements of some pictures of the power plants.  Petitioner does
not assert the existence of any private information in these pictures
of the power plants.  Rather, it focuses its attention on the details
of the nearby chemical manufacturing facilities that were also
captured on the film.  Petitioner has enlarged these photographs 20x
(see Sealed Joint Appendix, Photograph 5) and claims that the
enlargements that it itself produced so intrude into its private
concerns that the aerial photography must be held to violate the
Fourth Amendment.  In sum, the government has taken photographs that
do not appear to implicate any privacy concerns of petitioner;
petitioner in turn has manipulated those photographs to expose
information that it desires to keep private and now complains about
the attendant privacy intrusion.  /15/

   Petitioner's complaint therefore is about the potential privacy
intrusion created by the aerial photography here.  The Court has
recently rejected essentially the same contention, however, making
clear that the Fourth Amendment does not prohibit government activity
simply because of the information that could be revealed if further
activity were undertaken.  The fact that it may violate the Fourth
Amendment to monitor a beeper when it is located in a private
residence (see United States v. Karo, supra) does not mean that it is
unlawful to install the beeper in a container of chemicals that might
be taken into a private residence.  As long as the beeper is not
actually used to reveal information about the whereabouts of an item
in a private place that could not be learned through observation from
a place where the police have a right to be, its use for other
purposes not implicating protected privacy rights is lawful (see
United States v. Knotts, 460 U.S. at 285).  It is clear that
"potential, as opposed to actual, invasions of privacy (do not)
constitute searches for purposes of the Fourth Amendment. * * * It is
the exploitation of technological advances that implicates the Fourth
Amendment, not their mere existence." Karo, slip op. 6.  /16/

   Thus, even on the assumption that petitioner is correct that it
would violate its Fourth Amendment rights for the government to
observe the details of petitioner's chemical plant to the extent
revealed in the enlargements made by petitioner, the aerial
photography here would not be unconstitutional.  Petitioner's remedy
in such a case would be to challenge the government's use of any
unlawful enlargements that it might make;  there is no basis
whatsoever for the relief that petitioner obtained in this case -- an
injunction against government use of any of the photographs, including
the unenlarged photos of the exterior of the power plants that
apparently are not even alleged to intrude into any privacy interest.

   b. In any event, it would not violate the Fourth Amendment even if
the government had sought to enlarge and use the particular
photographs of the chemical plant of which petitioner complains.
Petitioner advances no discernible basis for determining when aerial
photography is too intrusive to meet constitutional standards.
Petitioner concedes that the Michigan Department of Natural Resources
has taken aerial photographs of its plant from an altitude of 12,000
feet (one of the altitudes at which the EPA photographs in this case
were taken) (see Br. 38;  J.A. A45-A47), but it dismisses these
photographs with the statement that the degree of detail that such
photographs show "does not cause Dow concern" (Pet. Br. 39).  /17/ The
lawfulness of a particular method of investigation cannot turn solely
on whether it causes the subject concern;  the Fourth Amendment
requires a more objective standard.  Petitioner's focus on its own
subjective desire is particularly inapt here, where the gist of its
complaint is directed not at the actual observations or photographs
made, but at the detail they potentially can reveal when enlarged and
magnified.  Presumably then, under petitioner's theory, if enlargement
and magnification technology were to improve, the heretofore
unobjectionable photographs taken by the State of Michigan might
suddenly turn into Fourth Amendment violations.  /18/

   In our view, the question whether an individual or corporation has
a legitimate expectation of privacy from a particular form of aerial
observation depends largely on the extent to which that form of
observation is available to the public.  If the technology to take a
particular type of aerial photograph is commonly available and society
has taken no steps to restrict or outlaw such photography, then an
individual can have no reasonable expectation that his outdoor
activity will not be photographed in this fashion by members of the
public.  If so, the Fourth Amendment does not prevent the government
from taking the same photographs.

   Unless all aerial photography is to be banned, there is no basis
for finding a Fourth Amendment violation in the pictures taken on
behalf of EPA.  The photographs were taken with ordinary, commercially
available, camera equipment.  /19/ No technology was used that is
secret or within the special competence of the government;  on the
contrary, the government hired a private contractor who could have
been hired by any member of the public, and the contractor used his
standard equipment.  /20/ When the aircraft flew over the plant, it
was well within the navigable airspace where Congress has guaranteed
its right to fly.  Any details of the outdoor portions of the plant
capable of being revealed by this photography (and we reiterate that
the government did not take the steps hypothesized by petitioner that
could reveal such details) cannot reasonably have been expected to
remain private.  If such photography is available to members of the
public, such as news magazines interested in petitioner's plant (see
Fish Stories and Empty Offices, Time, Apr. 11, 1983, at 18) the Fourth
Amendment surely does not prohibit the government from using such
photography in the exercise of its regulatory responsibilities.

 4. Society Does Not Recognize A Reasonable Expectation Of Privacy In
Outdoor Activity Strong Enough To Outweigh The Government Interest In
Using Aerial Photography

   As detailed above, application of the first prong of the Katz test
shows that no Fourth Amendment violation occurred here because
petitioner could not have a reasonable subjective expection of privacy
from common, commercially available, and generally lawful photography.
 The second prong of the Katz test, focusing on the nature of the
privacy interest at stake, also supports the decision of the court of
appeals.  The only areas observable from the air, no matter how
extensively photographs are enlarged or magnified, are ones that are
open to the sky.  Such outdoor areas ordinarily "do not provide the
setting for those intimate activities that the (Fourth) Amendment is
intended to shelter from government interference or surveillance."
Oliver, slip op. 7.  /21/

   To be sure, it is possible that a person may sometimes engage in an
essentially private activity in an outdoor setting.  The question is
whether it is reasonable from society's viewpoint for the Fourth
Amendment to protect from the fairly unlikely possibility of aerial
observation those occasional episodes of intimate activity that occur
outdoors (which are, of course, undertaken with knowledge that they
may be observable from the air).  This inquiry into the reasonableness
of aerial photography must be judged "by balancing its intrusion on
the individual's Fourth Amendment interests against its promotion of
legitimate governmental interests." Delaware v. Prouse, 440 U.S. 648,
654 (1979) (footnote omitted).  See also United States v.
Martinez-Fuerte, 428 U.S. 543, 555 (1976);  Camara v. Municipal Court,
387 U.S. 523, 536-537 (1967).

   We submit that it is not reasonable to use the Fourth Amendment in
the present context to erect a visual barrier where none exists in
fact.  There is a strong public interest in allowing the government to
use efficient and effective means in discharging its law enforcement,
regulatory, and other responsibilities.  The extremely limited privacy
interest in protecting from the possibility of aerial observation the
ordinary gamut of nonprivate outdoor activities such as the emission
of gases from a factory smokestack, and even the occasional outdoor
activity for which an individual might genuinely desire privacy,
cannot outweigh this government interest, particularly when private
citizens are in any event able to observe such activity from the air
without restriction.  The "balancing of competing interests" that is
the "key principle" in assessing reasonableness (see Michigan v.
Summers, 452 U.S. 692, 700 n.12 (1981), quoting Dunaway v. New York,
442 U.S. 200, 219 (1979)) tips overwhelmingly in favor of permitting
aerial observation and photography.

   The lack of constitutional protection of outdoor activity from
aerial observation does not mean that persons are unprotected by the
Fourth Amendment when they are outdoors.  Because of its association
with the home, this is particularly true when outdoor activity takes
place within the curtilage.  There it is entitled to the basic privacy
protection of freedom from entry and interference without just cause.
/22/ For many of the activities that might conceivably be conducted
outdoors, yet considered private, this protection against entry fully
satisfies any privacy interest that an individual might have.  A
prayer meeting, a moment of solitude, or a desire to protect fauna
from human intervention (see Oliver, slip op. 9 (Marshall, J.,
dissenting)) is significantly disturbed by an uninvited entry, yet is
hardly intruded upon, if at all, by mere observation from an
overflying aircraft.  Even the sort of outdoor activity that might be
considered intruded upon by observation, such as a lovers' tryst, is
obviously much more severely intruded upon by an actual entry.  Thus,
the decision below does not "wreak() havoc on protection for the home
and its attendant curtilage" (Pet. Br. 34).  On the contrary, given
the sorts of activities that are likely to take place in the
curtilage, a failure to prohibit aerial photography permits only a
fairly minimal intrusion into the privacy of those intimate activities
that are at the core of the Fourth Amendment.  See Oliver, slip op. 7.

   For the reasons discussed above, we submit that aerial photography
of the curtilage does not infringe an expectation of privacy that
society would regard as reasonable.  This case, however, does not even
involve the curtilage, and therefore it is even clearer here that
there is no basis for finding that the Fourth Amendment prohibits the
overflight that occurred.  The common law concept of curtilage is
particularly associated with the home, and its special Fourth
Amendment protection derives from the fact that the intimate
activities associated with the home may extend in some fashion to the
curtilage.  See note 3, supra.  That is plainly not the case with
petitioner's outdoor manufacturing plant.  The types of private
activities that might occur in the curtilage, or even in open fields
(see Oliver, slip op. 9 (Marshall, J. dissenting)), surely would never
take place within the confines of petitioner's manufacturing plant.
Indeed, if we put to one side for the moment the question of trade
secrets, which we discuss next, it is difficult to conceive of any
business-related activities likely to take place within the outdoor
surroundings of a manufacturing plant that would fall within the scope
of private activities that the Fourth Amendment is intended to
shelter.  Accordingly, there can be no justification for interpreting
the Fourth Amendment to protect the plant from aerial observation at
the expense of the considerable government interest in effective
regulation.  /23/

 5. The Existence Of A Trade Secret In An Outdoor Area Does Not
Convert Photography Of That Area Into A Fourth Amendment Violation

   The overriding theme of petitioner's contention in this Court is
that the photographs of the outdoor portions of its plant capture
"trade secrets" that are contained in the precise configuration of
pipes and equipment that fill the spaces between the enclosed
structures.  See Pet Br. 22-24, 35-39, 45-47.  Petitioner assets that
its interest in preventing dissemination of these trade secrets
confers upon it a constitutional right to be free from aerial
photography by the government.  While petitioner's premise strikes us
as doubtful, we will assume for present purposes that the
configuration of pipes does constitute a trade secret that is capable
of being revealed by the photographs taken by Abrams Aerial Survey.
/24/ The fact is, however, that the presence or absence of a trade
secret is completely irrelevant to the general Fourth Amendment issue
at hand.  /25/

   Both the common law and modern statutory law have recognized that
society has an interest in giving individual entrepreneurs proprietary
rights in the fruits of their labor and inventiveness.  It is thought
preferable for businessmen to develop products through innovation and
hard work, rather than by stealing the work product of a competitor.
Accordingly, some degree of protection of trade secrets has long been
a component of tort or unfair competition law.  Section 757(a) of the
Restatement of Torts (1939) states that "(o)ne who discloses or uses
another's trade secret, without a privilege to do so, is liable to the
other if he discovered the secret by improper means." As petitioner
notes, similar provisions are contained in Michigan law and in the
Uniform Trade Secrets Act.  See Br. 47-48;  Pet. App. C1-C2, D1-D6,
E1-E3.

   What petitioner fails to appreciate is that these rules are
directed solely at preventing unfair competition;  they do not purport
to establish any privacy interest and provide no guidance for the
Fourth Amendment inquiry.  The Restatement establishes tort liability
for one who "discloses or uses" a trade secret.  The Michigan statute
makes it a misdemeanor for one to steal a trade secret "with an intent
to appropriate a trade secret to his own use or to the use of
another." Mich. Comp. Laws Ann. Section 752.772 (West 1985);  Pet.
App. E3.  The Uniform Trade Secrets Act Sections 1-3, 14 U.L.A.
541-548 (1980), establishes a right to injunctive relief or damages
from misappropriation of a trade secret.  "Misappropriation" is
defined in terms of "disclosure and use" of a trade secret acquired
through improper means.  Pet. App. D1-D3.  /26/ Clearly, the essence
of the law's protection of trade secrets is the prohibition on unfair
destruction of the competitive advantage of the owner of the secret by
disclosing or using it.  See 4 Restatement of Torts Section 757
comment at 17 (1939).  This prohibition is consistent with the goal of
the rules to prevent unfair competition.

   Just as clearly, this case involves none of the considerations that
underlie the protection for trade secrets.  Putting aside the fact
that the government never sought to acquire the trade secret because
it was interested in the power plants, not extreme magnifications of
the chemical plants also captured on the film, it cannot seriously be
contended that there was any danger that the government would use the
trade secret.  The EPA is not in the business of building chemical
plants;  its business is to administer the anti-pollution laws and to
regulate emissions from manufacturing facilities.  Nor is it in the
business of supplying information about chemical manufacturing plants
to a company's competitors.  Thus, even if EPA inadvertently came into
possession of a trade secret in the course of its aerial photography
of petitioner's plant, it would not have violated the trade secret
statutes, which focus on disclosure or use, and its action should not
have given petitioner cause for concern that its secret had been
compromised.  /27/

   More generally, there is no reason why the Fourth Amendment ought
to be implicated simply because the government comes into possession
of trade secrets.  That occurs all the time in the course of the
normal functioning of government.  Statutes require companies to
furnish the government with information that may be classed as trade
secrets (see, e.g., Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA), 7 U.S.C. 136(a)), and the government may subpoena such
information for legitimate purposes (see, e.g., Wearly v. FTC, 616
F.2d 662 (3d Cir.), cert. denied, 449 U.S. 822 (1980)).  Legal
disputes arise over the government's power to disseminate such
information, which implicates the companies' interest in preserving
their trade secrets from competitors, but it has not heretofore been
suggested that it is unlawful for the government itself to take
possession of this information if it keeps it confidential.  See,
e.g., Ruckelshaus v. Monsanto Corp., No. 83-196 (June 26, 1984), slip
op. 20 n.13;  Wearly v. FTC, supra;  see also Chrysler Corp. v. Brown,
441 U.S. 281, 306 (1979).  Indeed, the practice of furnishing trade
secrets to the government is so pervasive that special statutes have
been enacted to protect against the possibility that they will be
unjustifiably disclosed.  See, e.g., 18 U.S.C. 1905 (Trade Secrets
Act);  5 U.S.C. 552(b)(4) (Freedom of Information Act).  The Clean Air
Act itself has a provision protecting trade secrets (42 U.S.C.
7414(c)), which indicates that Congress contemplated that EPA would
gain access to trade secrets in the course of its regulatory
activities.  /28/

   Petitioner cites dictum in a decision of this Court (Kewanee Oil
Co. v. Bicron Corp., 416 U.S. 470, 476 (1974)), and one court of
appeals decision, E.I. duPont deNemours & Co. v. Christopher, 431 F.2d
1012 (5th Cir. 1970), cert. denied, 400 U.S. 1024 (1971), for the
proposition that aerial observation is an "improper means" of
obtaining a trade secret.  See Pet. Br. 47-48.  Even if this premise
is correct, /29/ it does not follow that such observation is violative
of the Fourth Amendment.  First, it is not true that an action that
constitutes a tort thereby necessarily or even ordinarily constitutes
a Fourth Amendment violation.  See Oliver, slip op. 11-12.  Moreover,
because the policies involved in the two situations are so different,
there is no reason to suppose that the standards for deciding what is
an unfair means of obtaining a trade secret ought to have any bearing
on the reasonableness of an action under the Fourth Amendment.  The
purpose of the trade secret laws is to prevent unfair competition and
promote individual inventiveness.  Therefore, the law would quite
logically seek to prohibit the acquisition of trade secrets through
certain means that do not infringe at all upon the privacy interests
protected by the Fourth Amendment.

   The Restatement notes in its comments that means for acquiring
trade secrets may be improper "even though they do not cause any other
harm than that to the interest in the trade secret." 4 Restatement of
Torts Section 757 comment at 10-11 (1939).  For example, the
Restatement gives as illustrations of "improper means" of acquiring a
trade secret the use of a trespass or inducing employees to breach a
duty of confidence to their employer.  Ibid.  Deeming such methods
improper under the trade secret laws reasonably furthers the policies
of those laws;  indeed, the misappropriation before the Court in
Kewanee Oil, supra, was of this sort -- a breach of confidentiality by
former employees.  But it is plain that such activities do not violate
the Fourth Amendment.  It does not necessarily violate the
Constitution for police to obtain evidence by means of a trespass
(Oliver), and it surely is constitutional for police to obtain
information about a criminal enterprise from a former employee turned
informant or an undercover operative.  See, e.g., Hoffa v. United
States, 385 U.S. 293 (1966).  By the same token, even if unfair
competition law would hold it improper to use aerial observation or
photography for the purpose of acquiring a trade secret, that does not
suggest that it is unreasonable for the government to use aerial
observation to investigate criminal activity or in the exercise of its
other regulatory powers.

   In sum, neither the existence of a trade secret in an outdoor plant
nor any other activity likely to be carried on in such an area
implicates the sort of interest that the Fourth Amendment was designed
to protect.  Thus, both prongs of the Katz test suggest that
petitioner has no legitimate expectation of privacy from aerial
photography with commercially available equipment, and hence that the
Fourth Amendment does not prohibit such photography.  The technique is
freely available to the public, and therefore petitioner can have no
subjective expectation that its outdoor facility will not be
photographed from the air.  And the privacy interests implicated are
sufficiently slight that society would not regard it as reasonable to
protect them at the expense of constricting the government's ability
to utilize an effective technique that materially assists in the
exercise of important governmental functions.

 II. The Use Of Aerial Photography Does Not Exceed The Scope Of EPA'S
Statutory Authority

   Petitioner also contends (Br. 41-49) that, regardless of this
Court's resolution of the constitutional question, the overflight that
took place here was unlawful because EPA's statutory grant of
inspection authority does not authorize it to contract for aerial
photography.  /30/ This contention is devoid of textual or other
support, and the court of appeals was correct in rejecting it
sujmarily (see Pet. App. A13-A14).

   When Congress invests a government agency with law enforcement and
investigatory authority, it has never been suggested that Congress
must explicitly identify each and every lawful technique that might be
used in the course of an investigation.  Rather, it is naturally
assumed that the agency is entitled to use those methods of
investigation that could be undertaken by any member of the general
public.  Special authorization may be given to use methods that are
not available to the public.  For example, the Attorney General is
given special, express authority to seize private property pursuant to
warrant (18 U.S.C. 3107) and to engage in forcible entries in
connection with executing a warrant (18 U.S.C. 3109).  The enumeration
of these specific powers does not implicitly exclude from the Attorney
General's broad authority "to detect and prosecute crimes" (28 U.S.C.
533) the power to engage in more mundane investigatory activities,
such as following a person or car on the streets or questioning
witnesses to a crime.

   By the same token, the statutory power conferred on EPA to enforce
certain anti-pollution laws (see 42 U.S.C. 7413) must implicitly carry
with it the power to use ordinary, publicly available techniques to
gather relevant information.  There can be little doubt that EPA
officials can do research in the library, inspect public records of a
company's building permits at a local government office, place air
quality monitors on public property downwind from a pollution source,
or stand on the public highway and observe (or photograph) a pollution
source (see Air Pollution Variance Board v. Western Alfalfa Corp., 416
U.S. 861, 864-865 (1974)) -- all without specific statutory
authorization.  By the same token, they ought to be able to use aerial
photography to the same extent that that technique is lawfully
available to the general public.  Indeed, we are aware of no statute
that expressly confers upon a government agency the general authority
to use aerial photography for investigative or regulatory purposes,
but, as noted above (at 22-23), this technique is frequently used by
numerous agencies for diverse objectives, law enforcement and
otherwise.  Thus, there is no basis for petitioner's suggestion that
aerial photography by EPA is not authorized simply because it is not
specifically mentioned in the statute.

   Congress has conferred upon the EPA special investigative powers to
aid it in its enforcement mission.  Under Section 114 of the Clean Air
Act, 42 U.S.C. 7414, the EPA may prescribe recordkeeping requirements
and the installation of monitoring equipment.  More important, the
statute gives appropriate EPA officials the right to enter the
premises of any person who owns or operates an emission source in
order to look at these records, sample emissions, and generally
conduct an inspection.  There is no suggestion in the statute,
however, that the powers conferred by Section 114 are intended to be
exclusive.  /31/ Somewhat paradoxically, petitioner nonetheless claims
(Br. 43-45) that it is this additional grant of authority that
demonstrates that Congress has prohibited the EPA from engaging in
aerial photography.

   As with most administrative inspection statutes (see, e.g., 7
U.S.C. 136g (FIFRA);  15 U.S.C. 1270 (hazardous substances);  29
U.S.C. 657 (OSHA)), Section 114 of the Clean Air Act prescribes
certain procedures to be followed by agency officials in executing
their authority to enter private premises, which include presenting
their credentials.  It is hard to understand petitioner's contention,
however, that these requirements should be read to prohibit aerial
photography.  When agency officials seek access to private premises or
to inspect business records, it is obvious that they should identify
themselves since their right to enter depends on their status as
agents of the government acting pursuant to specific statutory
authority.  A member of the public would not be entitled to enter the
premises to inspect.  But when agency officials use some method of
investigation that is not an entry and that is available to a private
investigator or any other member of the general public and hence does
not require specific statutory authorization, there is no reason at
all for the entry procedures to apply.

   More generally, it is clear that 42 U.S.C. 7414 was enacted in 1970
with the intent of expanding the authority of government officials to
investigate air pollution.  See, e.g., Senate Comm. on Public Works,
93d Cong., 2d Sess., A Legislative History of the Clean Air Act
Amendments of 1970 829 (Comm. print 1974) (remarks of Rep. Murphy).
If petitioner's argument were correct, this provision would prohibit
EPA inspectors from standing on a public street and looking at the
smoke coming out of petitioner's factory.  But it would obviously be
anomalous to convert this positive grant of authority into an implicit
restriction on the EPA'S ability to use non-entry investigative
methods of the sort available to the general public, particularly when
the authority expressly conferred to enter premises at ground level is
undoubtedly more intrusive than observation from the public airspace
or any other location off petitioner's property.  In sum, there is no
statutory impediment to EPA's use of aerial observation in aid of its
regulatory functions.  /32/

                              Conclusion

   The judgment of the court of appeals should be affirmed.

   Respectfully submitted.

   LAWRENCE G. WALLACE

      Acting Solicitor General /*/

   F. HENRY HABICHT II

      Assistant Attorney General

   ANDREW L. FREY

      Deputy Solicitor General

   ALAN I. HOROWITZ

      Assistant to the Solicitor General

   DIRK D. SNEL

   ANNE S. ALMY

      Attorneys

   OCTOBER 1985

   /1/ Attorneys for the parties maintained access to the sealed
exhibits.  Petitioner's counsel took some of the film and had two
frames (Nos. 8505 and 9506) enlarged 10x and 20x, resulting in a scale
of 1 inch equals 10 feet.  These enlargements prepared by petitioner
are contained in the Sealed Joint Appendix, photographs 4 and 5.

   /2/ Petitioner's claims under the Fifth Amendment were later
dismissed without prejudice by stipulation of the parties.  C.A. App.
447-448.

   /3/ Petitioner's manufacturing plant does not fit within the
ordinary understanding of the term "curtilage," which is particularly
associated with the home.  In Oliver, the Court described the
curtilage as "the area to which extends the intimate activity
assocated with the 'sanctity of a man's home and the privacies of
life.'" Slip op. 8 (quoting Boyd v. United States, 116 U.S. 616, 630
(1886)).  The intimate activities associated with the home do not take
place in the outdoor areas of a manufacturing plant.  More generally,
"the expectation of privacy that the owner of commercial property
enjoys in such property differs significantly from the sanctity
accorded an individual's home." Donovan v. Dewey, 452 U.S. 594,
598-599 (1981).  Hence, petitioner's plant cannot be considered as
coming within the ambit of the common law concept of "curtilage." See,
e.g., United States v. Long, 674 F.2d 848, 853 (11th Cir. 1982);
United States v. Wolfe, 375 F. Supp. 949, 957-959 (E.D. Pa. 1974);
but cf. United States v. Swart, 679 F.2d 698 (7th Cir. 1982) (stating
that yard of auto repair shop may be "curtilage" and hence protected
from unconsented entry).  For present purposes, however, we will
assume that the grounds of petitioner's plant are entitled to a degree
of Fourth Amendment protection somewhat akin to, although not
necessarily identical to, that appropriate for the curtilage.  See
pages 36-37, infra.

   /4/ Suppose that in this case EPA agents had observed and
photographed petitioner's plant from the top of a nearby tall building
or water tower.  Plainly, there could be no tenable claim of a Fourth
Amendment violation in such circumstances.  For reasons explained in
the next point, the same action from the public airspace is
analytically indistinguishable.

   /5/ In this connection, we urge the Court to examine the
photographs taken for EPA and contained in the Sealed Joint Appendix
(Nos. 1, 2, and 3);  the suggestion that they reveal the kind of
private object or activity deserving of substantial Fourth Amendment
protection seems to us to be entirely belied by the photographs.

   /6/ This declaration of a public right of freedom of transit
through navigable airspace was repeated in the Civil Aeronautics Act
of 1938, ch. 601, Section 3, 52 Stat. 980, and in the Federal Aviation
Administration Act of 1958, Pub. L. No. 85-726, Section 104, 72 Stat.
740.  It is codified at 49 U.S.C. App. 1304.

   /7/ No minimum altitude is set for aircraft operating over open
water or sparsely populated areas, but such aircraft must remain 500
feet above any person, vehicle, or structure.  Helicopters may be
operated at lower altitudes than those specified for fixed wing
aircraft as long as they are operated without hazard to persons or
property on the ground.  14 C.F.R. 91.79.

   /8/ More than 1 million flight hours per year are devoted to the
purpose of "aerial observation." Census of U.S. Civil Aircraft, supra,
at 54.

   /9/ In light of the established, pervasive use of the aerial
highways, lower courts faced with the question have almost uniformly
held that aerial observation does not violate the Fourth Amendment.
See, e.g., United States v. Marbury, 732 F.2d 390, 398 (5th Cir.
1984);  United States v. Allen, 675 F.2d 1373, 1380-1381 (9th Cir.
1980), cert. denied, 454 U.S. 833 (1981);  United States v. Bassford,
601 F. Supp. 1324, 1328-1332 (D. Me. 1985);  United States v.
Mullinex, 508 F. Supp. 512, 514-515 (E.D. Ky. 1980);  United States v.
DeBacker, 493 F. Supp. 1078, 1081 (W.D. Mich. 1980);  State v. Knight,
63 Hawaii 90, 621 P.2d 370 (1980);  People v. Lashmett, 71 Ill. App.
3d 429, 431, 389, N.E.2d 888, 890 (1979), cert. denied, 444 U.S. 1081
(1980);  Williams v. State, 157 Ga. App. 476, cert. denied, 454 U.S.
823 (1981).  The courts that have found constitutional violations in
the context of aerial observation generally have done so in cases
where the overflights went below navigable airspace.  See, e.g.,
National Organization for the Reform of Marijuana Laws, Inc. v.
Mullen, 608 F. Supp. 945 (C.D. Cal. 1985);  People v. Sneed, 32 Cal.
App. 3d 535, 542-543, 108 Cal. Rptr. 146, 150-151 (1973).

   In People v. Ciraolo, 161 Cal. App. 3d 1081, 208 Cal. Rptr. 93
(1984), cert. granted, No. 84-1513 (June 3, 1985), the California
Court of Appeals appears to have established a broad rule that aerial
observation of the curtilage violates the Fourth Amendment in the
absence of probable cause and a warrant.  For the reasons discussed in
this brief, we believe that Ciraolo is wrongly decided and should be
reversed by this Court.

   /10/ Petitioner also asserts (Br. 38) that a camera can see what a
person cannot because looking through the floor of a plane is a
superior vantage point to looking out the window.  It may be true that
a passenger's view from a commercial air carrier is not very good as
compared to a floor-mounted camera.  But a passenger in a smaller
general aviation craft, which is the sort of aircraft that is likely
to fly low enough that items on the ground may be visible, has a much
greater range of vision and ordinarily would be able to have a
downward view similar to that of a camera.

   /11/ Aerial photographs are used extensively for mapping purposes,
and they have considerable utility in urban and regional planning
(see, e.g., Reynolds, Oblique Aerial Photography for Comprehensive
Urban Planning, Plan. Advisory Service Rep., May 1981, at 1;  W.
MacConnell & M. Cobb, Mass. Agricultural Experiment Station, Bull. No.
622, Remote Sensing 20 Years of Change in Middlesex County
Massachusetts, 1951-1971 (1974)) and highway location and design (see
Highway Design Division, Texas Highway Department, The Use of Maps
Compiled by Photogrammatic Methods (1966)).  See generally Wick,
supra, 1 Northrop U.L.J. at 116-117.

   /12/ If, for example, the government possessed a sophisticated
X-ray device that enabled it to see through the walls of a house,
there seems little doubt that the use of such a device to discover
objects or activities located inside a dwelling would be subject to
Fourth Amendment regulation.  That is because people can reasonably
expect privacy from such surveillance.  The same plainly cannot be
said with respect to the use of commonly available photographic
equipment to record outdoor activities or conditions.

   /13/ Petitioner relies heavily (see Br. 16, 25, 27-29, 37) on
United States v. Taborda, 635 F.2d 131 (2d Cir. 1980), and United
States v. Kim, 415 F. Supp. 1252 (D. Hawaii 1976), which found the use
of telescopes to violate the Fourth Amendment.  These cases, however,
are plainly inapposite here because they turned on the fact that the
telescopes were used to see inside the home, not to observe activity
occurring in the open air.  Taborda, 635 F.2d at 138-139;  Kim, 415 F.
Supp. at 1257-1258.  Whether or not these cases are correctly decided
on their facts, it is apparent that the fundamental Fourth Amendment
concern with the privacy of the home because of the intimate
activities that occur there justifies greater protection against the
use of technological visual aids than is appropriate in the case of
outdoor activities, even if they occur on the curtilage.  See United
States v. Hensel, 699 F.2d at 41;  United States v. Lace, 669 F.2d 46,
49-51 (2d Cir.), cert. denied, 459 U.S. 854 (1982).  See generally
pages 33-37, infra.

   /14/ In our view, the district court erred in exercising
jurisdiction over petitioner's suit, presumably on the basis of its
inherent equitable powers, rather than waiting for a concrete
controversy where the government actually tried to make use of some of
the information gathered during the overflight.  See Pieper v. United
States, 604 F.2d 1131 (8th Cir. 1979);  In re Worksite Inspection of
Quality Products, Inc., 592 F.2d 611, 613-617 (1st Cir. 1979);
Hunsucker v. Phinney, 497 F.2d 29 (5th Cir. 1974), cert. denied, 420
U.S. 927 (1975).  Moreover, even if there existed a sufficient
prospect of future warrantless aerial photography of petitioner's
facility to justify possible declaratory or prospective injunctive
relief, it is most doubtful that the injunction barring any use of the
photographs already taken could be proper.  It is by no means clear
that the exclusionary rule would apply to EPA regulatory proceedings
(cf. INS v. Lopez-Mendoza, No. 83-491 (July 5, 1984) or that, if it
did, it would bar consideration of evidence obtained in the mistaken
but "good faith" belief that the Fourth Amendment was not being
violated (cf. United States v. Leon, No. 82-1771 (July 5, 1984)).  The
propriety of EPA's use of the photographs in such a manner would be
best determined in connection with any proceeding in which such use
was sought to be made.

   /15/ The difference between the magnified enlargements upon which
petitioner focuses its attention and the actual photographs possessed
by the government is dramatic.  Petitioner apparently regards
enlargements that show items as small as 1/2 inch in diameter to be
unconstitutionally intrusive (see Pet. Br. 12 n.*, 14).  The original
contact prints made by the government in this case of the photographs
taken at the lowest altitude were at a scale of 1 inch equals 200 feet
(Pet. Br. 12).  Thus, on these prints a half-inch item would measure
1/4800 of an inch.  The district court found that these prints could
be enlarged to a scale of 1 inch equals 20 feet without significant
loss of resolution (Pet. App. B3;  see Pet. Br. 12;  J.A. A59).  Even
at the scale of these potential enlargements, the items in question
would measure only 1/480 of an inch on the photograph.

   /16/ Under petitioner's suggestion, as technology improved, there
would paradoxically be a reduction in the degree of technology
available to government officials.  For example, under Lopez v. United
States, supra, the police are permitted to record a conversation
between a suspect and an informant.  Suppose it were possible through
the use of advanced technology to amplify that recording and suppress
interference to the extent that a conversation taking place in the
adjoining room could be made audible.  Petitioner's contention would
lead to the perverse result that the possibility of such enhancement
would invalidate the act of recording itself and require that Lopez be
overruled.  Indeed, petitioner's argument, if carried to its logical
limit, could have ramifications even outside the context of
technological enhancement.  It would suggest that an otherwise lawful
seizure of an item could violate the Fourth Amendment because it
creates the potential for an unlawful search or viewing of the item.
Compare Walter v. United States, 447 U.S. 649 (1980);  United States
v. Chadwick, 433 U.S. 1, 13-14 n.8 (1977).

   /17/ In light of this concession, it is unclear how petitioner
could have sought, and obtained from the district court, an injunction
prohibiting EPA from using any of the photographs taken by Abrams
Aerial Survey.  Some of these photographs were taken at 12,000 feet
(see J.A. A39, A45) and thus approximate the photographs taken by the
Michigan state agency.

   /18/ Even with the technology commonly available today, the
altitude at which a plane flies is only one factor that determines the
detail potentially exposed to the photographer.  That level of detail
will also depend on the type of camera and the degree of enlargement.
For example, the photographs taken by the state officials, if enlarged
10x, would be on the same scale as the EPA pictures taken from the
lowest altitude here -- pictures that the district court enjoined the
government from using.

   /19/ Indeed, the record indicates that photographs showing greater
detail than those taken here could have been taken from a helicopter
with a good quality 35 millimeter camera and a standard 70 millimeter
lens (J.A. A48-A50).

   /20/ An urban planner discussing the utility of aerial photography
reports that his local planning department purchased from Abrams
Aerial Survey Corporation vertical aerial photographs of the entire
West Bloomfield Township area in Michigan.  The county planning
commission made available photographs of the populated area at an
original scale of 1 inch equals 100 feet, i.e., twice as detailed as
the most detailed pictures taken for EPA in this case.  See Reynolds,
supra, Plan. Advisory Service Rep. at 4-5.

   /21/ Despite petitioner's efforts to equate the two cases (see Br.
16, 25, 27), the difference in the nature of the activity sought to be
protected makes this case fundamentally unlike Katz.  In Katz, the
question was the government's right to overhear "private
communication" (389 U.S. at 352), the sort of activity that lies at
the core of the privacy interests valued by our society.  Therefore,
the Court found that an individual who uses a phone booth "is surely
entitled to assume that the words he utters into the mouthpiece will
not be broadcast to the world" (ibid).  A fundamental aspect of
privacy would be lost if people had no ability to keep their private
conversations from being overheard at the whim of the government.  No
comparable loss of privacy occurs if persons are subject to the
possibility of aerial observation when they are outdoors.

   /22/ This protection against entry serves the dual purpose of
protecting property and activities located on the curtilage from
interference and providing a buffer that enhances the privacy and
security of the home itself.

   /23/ Petitioner complains (Br. 6, 32-33;  see also Pet. App. G1-G2)
that it is economically infeasible for it to take measures to insulate
its plant from aerial observation.  It hardly follows from that
premise, however, that the Constitution must pick up the slack and
serve as a roof for the plant.  A more reasonable deduction would be
that the practical impossibility of protecting petitioner's outdoor
activity from observation merely evidences the fact that the activity
cannot reasonably be reagrded as "private" and therefore is not the
sort of activity at which the constitutional protection is directed.

   /24/ The existence of a trade secret in this case was in part at
least an issue of fact that was disputed by the parties.  For this
reason, the district court did not dispose of petitioner's Fifth
Amendment claim on summary judgment.  See Pet. App. B38.  The Fifth
Amendment claim was later dismissed without prejudice, and therefore
this factual dispute has not been resolved.  In any event, we think it
highly doubtful as a matter of law, that it is possible to have a
trade secret that is so easily observable from the air.  See note 29,
infra.

   /25/ Moreover, we note that the significance of petitioner's trade
secret claims to this particular litigation seems to be greatly
overstated.  EPA policy, reflected in published regulations (40 C.F.R.
2.119(b)), is to protect, not release, trade secret information.
Rather than requesting that EPA preserve the confidentiality of this
information, however, petitioner chose to institute this lawsuit.
Furthermore, the relief sought and obtained by petitioner goes well
beyond what is relevant to protecting its trade secret.  It seems
apparent, therefore, that petitioner wishes to prevent EPA overflights
quite apart from any question of trade secrets.

   /26/ Section 1(2)(i) of the Act, 14 U.L.A. 541 (1980), arguably
suggests that acquisition of a trade secret can alone constitute
actionable misappropriation.  The full context of the statute,
however, makes clear that the statute contemplates either disclosure
or use of the trade secret as the basis for a suit under the statute.
The basic injunctive relief available is an injunction against future
use and disclosure (see Section 2(b) and Commissioners' Comment, 14
U.L.A. 544 (1980)), and it is difficult to imagine what damages could
be available (Section 3) without disclosure or use by a competitor.
To the extent mere acquisition implicates the statute, it is
acquisition with the intent to appropriate a trade secret, which can
be guarded against by a suit to enjoin disclosure or use of the secret
-- relief far narrower than that sought and obtained from the district
court by petitioner.

   /27/ Petitioner's argument in this regard highlights again the
inappropriateness of considering its privacy claim in the abstract,
rather than in the specific context of a government attempt to use the
information it has obtained.  There appears to be no claim that
petitioner has any trade secret in the power plants that were the
target of the government's aerial observation.  Thus, to the extent
petitioner's Fourth Amendment claim rests on the presence of a trade
secret, petitioner would appear to have no objection to the overflight
if the camera had been more discriminating and the photographer had
been able to limit his photographs to the target power plants.  But
that situation ought not to be treated differently from the one
actually presented here, where the government allegedly has
inadvertently obtained the capability to examine photographs of a
trade secret but has no intention of actually doing so, much less
making use of the trade secret.  Under petitioner's theory, a
marijuana farmer could protect his fields from aerial observation by
placing some trade secret in the midst of the marijuana.  Cf. Oliver,
slip op. 11 n.13.

   /28/ There is always the theoretical possibility, of course, that a
trade secret in the possession of the government will be disclosed
inadvertently.  Thus, it is understandable that petitioner would
prefer that the government not obtain possession of any trade secret,
even if it has no intention to use it or disclose it.  Because of this
danger of inadvertent disclosure, it might be said that the
government's mere acquisition of a trade secret constitutes some
invasion of petitioner's rights (although it would appear to be more
its property right in the trade secret than any right protected by the
Fourth Amendment).  Even if that is true, however, it cannot seriously
be doubted that the strong government interests implicated here would
outweigh such a small, speculative effect on petitioner's rights.
Unfortunately, in today's society, manufacturing facilities frequently
produce toxic chemicals that pollute the environment.  For example,
EPA tests have indicated that waste water discharged by petitioner's
Midland facility into an adjacent river contains more than 40 toxic
chemicals.  See N.Y. Times, Apr. 1, 1983, at A1, col. 1.  The strong
public interest in enforcing the statutes that regulate this type of
pollution outweighs the possibility that information obtained from
aerial photography might also contain a trade secret that might
inadvertently be disclosed.

   /29/ The Christopher decision is actually somewhat narrower than
described by petitioner.  In that case aerial photographs were taken
of a plant under construction, and it was not contested that they were
taken for the purpose of appropriating a process that DuPont sought to
keep secret.  The court, in finding that DuPont had an action under
Texas law for misappropriation of a trade secret, relied heavily on
the fact that the photographer had used the "trick" (431 F.2d at 1016)
of flying over the plant before it could be completed.  The court
explained that "after construciton the finished plant would have
protected much of the process from view, (but) during the period of
construciton the trade secret was exposed to view from the air"
(ibid.).  See also Hurst v. Hughes Tool Co., 634 F.2d 895, 898 (5th
Cir. 1981).  Thus, Christopher does not really address the question
whether it is improper to appropriate a trade secret by flying over a
completed facility that is so constructed that the alleged "secret" is
visible to the aerial observer or photographer.  Specifically,
Christopher does not resolve whether, in light of the fact that "the
extent of the property right (in a trade secret) is defined by the
extent to which the owner of the secret protects his interests from
disclosure to others" (Ruckelshaus v. Monsanto Co., slip op. 13), a
company can have a trade secret in an outdoor plant that is readily
subject to aerial observation.  Thus, in this case, it is doubtful
both as a legal and factual (see note 24, supra) matter whether
petitioner has a trade secret in the configuration of its outdoor
facility.  For purposes of the issues presented here, however, we will
assume arguendo that petitioner does have such a trade secret.  As
discussed in text, whether or not private competitors may use aerial
photography to appropriate information claimed to be a trade secret
has no bearing on whether the Fourth Amendment prohibits the
government from using aerial photography for other purposes.

   /30/ We assume, for purposes of this discussion, that aerial
photography does not violate the Fourth Amendment.  If the overflight
here were unconstitutional, we would not contend that the statute must
be construed to authorize it, and, in any event, the issue would be
insignificant because, regardless of Congress's intent, the overflight
would be unlawful.  For this reason, we regard as quite irrelevant
petitioner's assertion (Br. 46) that the EPA cannot use "other
constitutionally offensive scrutiny, such as intrusive aerial
photography, which Congress did not specifically list as forbidden."
We do not dispute that the EPA cannot use "constitutionally offensive
scrutiny";  the issue is whether, as a matter of statutory authority,
the EPA may use constitutionally permissible aerial photography.
Thus, as petitioner's own characterization reveals, the fact that the
EPA cannot use wiretapping without explicit congressional
authorization has no bearing on the issue here because that is an
investigative technique that is not available to the public, but
rather is subject to stringent constitutional and statutory
limitations.  See Berger v. New York, 388 U.S. 41 (1967);  Omnibus
Crime Control and Safe Streets Act, 18 U.S.C. 2510 et seq.

   /31/ The enforcement provision of the statute is broadly worded to
authorize the Administrator of EPA to act on the basis of "any
information available to him," which seems to contemplate that he will
receive information from sources other than those specified in Section
114.  See 42 U.S.C. 7413(a)(1), (2) and (3).

   /32/ Petitioner also asserts (Br. 47) that allowing EPA to engage
in aerial photography would be inconsistent with the Clean Air Act's
provision protecting against disclosure of trade secrets.  Section
114(c), 42 U.S.C. 7414(c).  This contention is difficult to
comprehend.  A specific statutory provision protecting trade secrets
hardly suggests a limitation on investigative techniques;  on the
contrary, it presupposes that in using its investigative powers the
EPA will acquire information that may require protection.  See
Marshall v. Barlow's, Inc., 436 U.S. 307, 339 n.10 (1978) (Stevens,
J., dissenting).

   It may be that petitioner is contending that the protections of
Section 114(c) would not apply to aerial photography (because by its
terms that subsection applies only to "information obtained under
subsection (a)") and hence that the use of aerial photography is
inconsistent with the Act's recognition of the need to protect trade
secrets.  This argument is flawed.  Regardless of the applicability of
the disclosure and associated trade secret protections of Section
114(c), such trade secrets (if they exist) would still be protected
from disclosure under the Trade Secrets Act, 18 U.S.C. 1905, and the
Freedom of Information Act, 5 U.S.C. 552(b) (4) (see Chrysler Corp. v.
Brown, 441 U.S. at 318;  40 C.F.R. 2.119(b)).  Indeed, the protection
afforded under these statutes appears to be even broader than that
under Section 114(c), which excludes "emissions data." The EPA has
detailed regulations addressing the need to protect confidential
business matters (see 40 C.F.R. 2.201 et seq.), and it has
specifically addressed the issue of overflights.  In May 1978, EPA
adopted a policy of promptly notifying companies of overflights in
order to give them an opportunity at the outset to claim trade secret
protection.  See C.A. App. 160.

   Finally, as discussed above (see pages 37-42, supra), trade secrets
are not a genuine concern unless they are used or disclosed;  the
statutory protection for trade secrets surely does not suggest that
EPA is prohibited from taking photographs for its own legitimate
internal use.  In short, the existence of trade secret protection is a
complement to the EPA's ability to gather information through aerial
observation, not a prohibition on that method.

   /*/ Acting Solicitor General Fried is disqualified in this case.