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ADVANCING JUSTICE THROUGH DNA TECHNOLOGY: USING DNA TO SOLVE CRIMES

TOC | Executive Summary | Using DNA to Protect the Innocent

USING DNA TO SOLVE CRIMES

        The past decade has seen great advances in a powerful criminal justice tool: deoxyribonucleic acid, or DNA.  DNA can be used to identify criminals with incredible accuracy when biological evidence exists.  By the same token, DNA can be used to clear suspects and exonerate persons mistakenly accused or convicted of crimes.  In all, DNA technology is increasingly vital to ensuring accuracy and fairness in the criminal justice system.

        News stories extolling the successful use of DNA to solve crimes abound.  For example, in 1999, New York authorities linked a man through DNA evidence to at least 22 sexual assaults and robberies that had terrorized the city.  In 2002, authorities in Philadelphia, Pennsylvania, and Fort Collins, Colorado, used DNA evidence to link and solve a series of crimes (rapes and a murder) perpetrated by the same individual.  In the 2001 “Green River” killings, DNA evidence provided a major breakthrough in a series of crimes that had remained unsolved for years despite a large law enforcement task force and a $15 million investigation.

        DNA is generally used to solve crimes in one of two ways.  In cases where a suspect is identified, a sample of that person’s DNA can be compared to evidence from the crime scene.  The results of this comparison may help establish whether the suspect committed the crime.  In cases where a suspect has not yet been identified, biological evidence from the crime scene can be analyzed and compared to offender profiles in DNA databases to help identify the perpetrator.  Crime scene evidence can also be linked to other crime scenes through the use of DNA databases. 

        For example, assume that a man was convicted of sexual assault.  At the time of his conviction, he was required to provide a sample of his DNA, and the resulting DNA profile was entered into a DNA database.  Several years later, another sexual assault was committed.  A Sexual Assault Nurse Examiner worked with the victim and was able to obtain biological evidence from the rape.  This evidence was analyzed, the resulting profile was run against a DNA database, and a match was made to the man’s DNA profile.  He was apprehended, tried, and sentenced for his second crime.  In this hypothetical case, he was also prevented from committing other crimes during the period of his incarceration.

        DNA evidence is generally linked to DNA offender profiles through DNA databases.  In the late 1980s, the federal government laid the groundwork for a system of national, state, and local DNA databases for the storage and exchange of DNA profiles.  This system, called the Combined DNA Index System (CODIS), maintains DNA profiles obtained under the federal, state, and local systems in a set of databases that are available to law enforcement agencies across the country for law enforcement purposes.  CODIS can compare crime scene evidence to a database of DNA profiles obtained from convicted offenders.  CODIS can also link DNA evidence obtained from different crime scenes, thereby identifying serial criminals.   

        In order to take advantage of the investigative potential of CODIS, in the late 1980s and early 1990s, states began passing laws requiring offenders convicted of certain offenses to provide DNA samples.  Currently all 50 states and the federal government have laws requiring that DNA samples be collected from some categories of offenders.

        When used to its full potential, DNA evidence will help solve and may even prevent some of the Nation’s most serious violent crimes.  However, the current federal and state DNA collection and analysis system needs improvement:

(1) In many instances, public crime labs are overwhelmed by backlogs of unanalyzed DNA samples.
 
(2) In addition, these labs may be ill-equipped to handle the increasing influx of DNA samples and evidence.  The problems of backlogs and lack of up-to-date technology result in significant delays in the administration of justice.
 
(3) More research is needed to develop faster methods for analyzing DNA evidence.
 
(4) Professionals working in the criminal justice system need additional training and assistance in order to ensure the optimal use of DNA evidence to solve crimes and assist victims.

President Bush believes we must do more to realize the full potential of DNA technology to solve crime and protect the innocent.  Under the President’s initiative, the Attorney General will improve the use of DNA in the criminal justice system by providing funds and assistance to ensure that this technology reaches its full potential to solve crimes. 

1.      Eliminating Backlogs      Top

        One of the biggest problems facing the criminal justice system today is the substantial backlog of unanalyzed DNA samples and biological evidence from crime scenes, especially in sexual assault and murder cases.  Too often, crime scene samples wait unanalyzed in police or crime lab storage facilities.  Timely analysis of these samples and placement into DNA databases can avert tragic results.  For example, in 1995, the Florida Department of Law Enforcement linked evidence found on a rape-homicide victim to a convicted rapist’s DNA profile just eight days before he was scheduled for parole.  Had he been released prior to being linked to the unsolved rape-homicide, he may very well have raped or murdered again.

        By contrast, analysis and placement into CODIS of DNA profiles can dramatically enhance the chances that potential crime victims will be spared the violence of vicious, repeat offenders.  The President’s initiative calls for $92.9 million to help alleviate the current backlogs of DNA samples for the most serious violent offenses – rapes, murders, and kidnappings – and for convicted offender samples needing testing.  With this additional federal backlog reduction funding, the funding provided by this initiative to improve crime laboratory capacity, and continued support from the states, the current backlogs will be eliminated in five years.

Understanding the Backlog

        The state and local backlog problem has two components: (1) “casework sample backlogs,” which consist of DNA samples obtained from crime scenes, victims, and suspects in criminal cases, and (2) “convicted offender backlogs,” which consist of DNA samples obtained from convicted offenders who are incarcerated or under supervision.  The nature of the DNA backlog is complex and changing, and measuring the precise number of unanalyzed DNA samples is difficult. 

  • Casework Sample Backlogs:  In a 2001 survey of public DNA laboratories, the Bureau of Justice Statistics (BJS) found that between 1997 and 2000, DNA laboratories experienced a 73% increase in casework and a 135% increase in their casework backlogs.  Many casework samples go unanalyzed for lack of a suspect to which to compare the biological evidence from the crime scene.  These are often referred to as “no-suspect” cases.  Based on an ongoing assessment of crime laboratories and law enforcement agencies, the National Institute of Justice (NIJ) estimates that the current backlog of rape and homicide cases is approximately 350,000.  The initiative calls for $76 million in FY 2004 to help eliminate these backlogs over five years.
     
  • Convicted Offender Backlogs:  States are increasing the number of convicted offenders required to provide DNA samples.  Currently, 23 states require all convicted felons to provide DNA samples.  Preliminary estimates by NIJ place the number of collected, untested convicted offender samples at between 200,000 and 300,000.  NIJ also estimates that there are between 500,000 and 1,000,000 convicted offender samples that are owed, but not yet collected. The initiative calls for $15 million in FY 2004 to help eliminate convicted offender backlogs over five years.

         The federal government also faces a high demand for analysis of casework and convicted offender DNA samples.  The FBI has two DNA casework analysis units (see page 5).  The first unit, which focuses on analyzing nuclear DNA, has a backlog of approximately 900 cases.  The second unit, which focuses on analyzing mitochondrial DNA (mtDNA), has a backlog of roughly 120 cases.

        The federal government also collects DNA samples from persons convicted of offenses in certain categories, including crimes of violence or terrorism.  The FBI currently has a backlog of approximately 18,000 convicted offender samples.  The initiative calls for $1.9 million in FY 2004 to fund the federal convicted offender program; some of these funds will be devoted to eliminating the federal convicted offender backlog.

Effect of Clearing the Backlog

        The results of addressing backlogs are dramatic, as the two examples below illustrate:

  • In September 1993, a married couple was attacked on a jogging trail in Dallas by a man with a gun who sexually assaulted the woman after shooting the man.  No suspect was ever positively identified, although police investigated over 200 leads and 40 potential suspects. In August 2000, evidence from the case was analyzed using current DNA technology.  Then, in February 2001, the DNA sample was matched to an individual who was already serving a five-year sentence for an unrelated 1997 sexual assault of a child.  The man has since been convicted of capital murder and aggravated sexual assault.
     
  • In March 1992, an Alexandria, Virginia shop owner was stabbed more than 150 times in her home.  There were no witnesses to the crime.  For years, detectives had no leads, but they did have traces of someone’s blood, apparently from the fierce struggle between the victim and the killer.  Meanwhile, in 1996, a man pleaded guilty to robbing a gas station, and his DNA was collected for analysis and inclusion in the Virginia DNA database.  Because of the backlog, the man’s sample was not immediately analyzed.  In the summer of 2000, the sample was analyzed and matched through the database to the evidence from the Alexandria woman’s murder.  In April 2001, almost nine years after the commission of this brutal crime, the man was sentenced to life in prison.  

        Several law enforcement agencies, prosecutors’ offices, and crime labs across the country have established innovative programs to review old cases.  Often called “cold case units,” these programs have enabled criminal justice officials to solve cases that have languished for years without suspects. Most frequently, DNA evidence has been the linchpin in solving these cases.  For instance, this past July, a California man was found guilty of the 1974 rape-homicide of a 19 year-old pregnant woman – a case that was solved through DNA evidence nearly thirty years after the crime was committed.

Prior Federal Support of State DNA Backlog Reduction

        In recent years, the federal government has strongly supported states in their efforts to eliminate backlogs of convicted offender and casework DNA samples.  Since the creation in 2000 of the Department of Justice’s (DOJ’s) Convicted Offender DNA Backlog Reduction Program, more than 493,600 offender samples from 24 states have been analyzed.  Since the creation in 2001 of the No Suspect Casework DNA Backlog Reduction Program, federal funds have been provided to support the analysis of approximately 24,800 cases.  States have analyzed evidence in an additional 18,000 "no-suspect" cases as a result of a match requirement of Convicted Offender DNA Backlog Reduction funding.

        In 2002 and 2003 combined, the President requested and Congress appropriated $70.8 million to fund these DNA backlog reduction programs.  Additionally, Attorney General John Ashcroft also made available $25 million in Asset Forfeiture funds to address the backlog of convicted offender and "no suspect" casework samples.  Thus, the Bush Administration already has devoted more than $95 million to reducing DNA backlogs.   

2.      Strengthening Crime Laboratory Capacity       Top

        At present, many of our Nation’s crime laboratories do not have the capacity necessary to analyze DNA samples in a timely fashion.  Many have limited equipment resources, outdated information systems, and overwhelming case management demands.  As a result, the criminal justice system as a whole is unable to reap the full benefits of DNA technology.  The President’s initiative will provide federal funding to further automate and improve the infrastructure of federal, state, and local crime labs so they can process DNA samples efficiently and cost-effectively.  These infrastructure improvements are critical to preventing future DNA backlogs, and to helping the criminal justice system realize the full potential of DNA technology. 

Increasing the Analysis Capacity of Public Crime Labs

        The President’s initiative will provide significant support to public crime labs so that these labs can update their infrastructure, automate their DNA analysis procedures, and improve their retention and storage of forensic evidence. The initiative calls for $60 million in FY 2004 funding, which will be dedicated to: 

  • Providing Basic Infrastructure Support:  Some public crime laboratories still need assistance to help them obtain equipment and material to conduct the basic processes of DNA analysis – extraction, quantitation, amplification and analysis – and to help them meet various accreditation requirements.
     
  • Building Infrastructure through Laboratory Information Management Systems:  Laboratory Information Management Systems, or “LIMS,” are designed to automate evidence handling and casework management, to improve the integrity and speed of evidence handling procedures, and to ensure proper chain of custody.  DOJ estimates that only 10 percent of the public DNA laboratories have LIMS systems.
     
  • Providing Automation Tools to Public DNA Laboratories:  To streamline aspects of the DNA analysis procedure that are labor and time-intensive, crime laboratories should have automated systems, such as robotic DNA extraction units.  Automated DNA analysis systems increase analyst productivity, limit human error and reduce contamination.
     
  •  Providing Support for the Retention and Storage of Forensic Evidence:  Forensic evidence must be stored in a manner that ensures its integrity and maintains its availability throughout criminal investigations and judicial proceedings.  Appropriate evidence storage conditions require costly equipment such as security systems, environmental control systems, ambient temperature monitors, and de-humidifiers.  The initiative will support the improvement of evidence storage capabilities. 

Funding the FBI Forensic Analysis Programs

        The FBI Laboratory runs several different programs for the analysis of DNA information.  The Nuclear DNA Program supports federal, state, local, and international law enforcement agencies by providing advanced technical assistance within the forensic biology discipline and sub-disciplines through interrelated capabilities and expertise.  The Mitochondrial DNA (mtDNA) Analysis Program is responsible for performing mtDNA analysis of forensic evidence containing small or degraded quantities of DNA on items of evidence submitted from federal, state, and local law enforcement agencies.  Mitochondrial DNA is a powerful tool available for investigating cases of kidnapping, missing persons, and skeletal remains where nuclear DNA is not present.  The initiative will provide funds to these two existing programs to permit them to continue their important work.  In addition, the initiative will provide funds to the FBI to further expand regional mtDNA labs that will provide an alternative source for mtDNA analysis to state and local law enforcement, and allow the FBI laboratory to concentrate more of its efforts on federal cases.  The initiative calls for $20.5 million in FY 2004 to fund these programs.

Funding the Combined DNA Index System

        The Combined DNA Index System (CODIS), administered by the FBI, maintains DNA profiles obtained through federal, state, and local DNA sample collection programs, and makes this information available to law enforcement agencies across the country for law enforcement identification purposes.  Currently, the National DNA Index System (NDIS) of CODIS contains about 1.7 million DNA profiles.  The President’s initiative includes funding to complete a general redesign and upgrade of CODIS, which will increase the system's capacity to 50 million DNA profiles, reduce the search time from hours to microseconds for matching DNA profiles, and enable instant, real‑time (as opposed to weekly) searches of the database by participating forensic laboratories.  The initiative calls for $9.9 million in FY 2004 to fund this program.

3.          Stimulating Research And Development      Top

        In order to improve the use of DNA technology to advance the cause of justice, the Attorney General will stimulate research and development of new methods of analyzing DNA samples under the President’s initiative.  Also, the President has asked the Attorney General to establish demonstration projects under the initiative to further study the public safety and law enforcement benefits of fully integrating the use of DNA technology to solve crimes.  Finally, the President has directed the Attorney General to create a National Forensic Science Commission to study rapidly evolving advances in all areas of the forensic sciences and to make recommendations to maximize the use of the forensic sciences in the criminal justice system.  In all, the President’s initiative will devote $24.8 million in FY 2004 to fund advances in the use of DNA technology.

Improving DNA Technology

        Forensic DNA analysis is rapidly evolving.  Research and development of tools that will permit crime laboratories to conduct DNA analysis quickly is vital to the goal of improving the timely analysis of DNA samples.  Smaller, faster, and less costly analysis tools will reduce capital investments for crime laboratories while increasing their capacity to process more cases.  Over the course of the next several years, DNA research efforts will focus on the following areas:

  • The development of “DNA chip technology” that uses nanotechnology to improve both speed and resolution of DNA evidence analysis.  This technology will reduce analysis time from several hours to several minutes and provide cost-effective miniaturized components.
     
  • The development of more robust methods to enable more crime labs to have greater success in the analysis of degraded, old, or compromised items of biological evidence.
     
  • Advanced applications of various DNA analysis methods, such as automated Short Tandem Repeats (STRs), Single Nucleotide Polymorphisms (SNPs), mitochondrial DNA analysis (mtDNA), and Y-chromosome DNA analysis. 
     
  • The use of animal, plant, and microbial DNA to provide leads that may link DNA found on or near human perpetrators or victims to the actual perpetrator of the crime.
     
  • Technologies that will enable DNA identification of vast numbers of samples occasioned by a mass disaster or mass fatality incident.
     
  • Technologies that permit better separation of minute traces of male sexual assailant DNA from female victims.

        The initiative devotes $10 million in FY 2004 funding to benefit the state and local criminal justice community through DNA research and development.  It also requests $9.8 million in FY 2004 funding to further expand the FBI’s DNA research and development program.

Establishing DNA Demonstration Projects

        To further research the impact of increased DNA evidence collection on public safety and law enforcement operations, the Attorney General will conduct rigorous scientific research through demonstration projects on the use of DNA evidence under the initiative. This research will help determine the scope of public safety benefits that result when police are trained to more effectively collect DNA evidence and prosecutors are provided with training to enhance their ability to present this evidence in court.

        Several jurisdictions will be selected to incorporate core training and evidence collection requirements in their daily operations.  At each site, one or more law enforcement agencies will be chosen to implement extensive training on the collection of DNA evidence and to increase the resources devoted to the investigation and prosecution of these cases.  Prosecutors will also receive training on how to more effectively present DNA evidence and how forensic DNA technology may be used to solve current and “cold” cases.  Jurisdictions that received increased training and resources will be compared with  jurisdictions that did not receive these benefits. 

        The resulting comparison will measure the impact of increased DNA evidence collection on public safety and law enforcement operations.  For example, projects will examine whether there are increased crime clearance rates, whether DNA aided investigations, the number of cases successfully prosecuted, the number of cases where guilty pleas were obtained due to the presence of DNA evidence, any financial savings resulting from the use of forensic evidence, and increased responsiveness to victims.  The information obtained will allow state and local governments to make more informed decisions regarding investment in forensic DNA as a crime-fighting tool.  The initiative calls for $4.5 million in FY 2004 to fund these projects.

Creating a National Forensic Science Commission

        To facilitate the ability of policymakers to assess the needs of the forensic science community, and to stimulate public awareness of the uses of forensic technology to solve crimes, the President has directed the Attorney General to create a National Forensic Science Commission.  The Commission will be charged with two primary responsibilities: (1) developing recommendations for long-term strategies to maximize the use of current forensic technologies to solve crimes and protect the public, and (2) identifying potential scientific breakthroughs that may be used to assist law enforcement.  

        The Attorney General will appoint Commission members from professional forensic science organizations and accreditation bodies and from the criminal justice community.  These individuals will have broad knowledge and in-depth expertise in the criminal justice system and in various areas of the forensic sciences such as analytical toxicology, trace evidence, forensic biology, firearms and toolmark examinations, latent fingerprints, crime scene analysis, digital evidence, and forensic pathology, in addition to DNA.  Judges, prosecutors, attorneys, victim advocates, and other members of the criminal justice system will also be represented on the Commission. 

        The Commission will study advances in all areas of the forensic sciences and make recommendations on how new and existing technologies can be used to improve public safety.  The Commission will also serve as an ongoing forum for discussing initiatives and policy, and may issue recommendations that will assist state and local law enforcement agencies in the cost-effective use of these technologies to solve crimes.  The initiative devotes $500,000 in FY 2004 to the establishment of the Commission.

4.     Training the Criminal Justice Community      Top

        In order to maximize the use of DNA technology, under the President’s initiative, the Attorney General will develop training and provide assistance regarding the collection and use of DNA evidence to the wide variety of professionals involved in the criminal justice system, including police officers, prosecutors, defense attorneys, judges, forensic scientists, medical personnel, victim service providers, corrections officers, and probation and parole officers.  

        Key players in the criminal justice system should receive additional training in the proper collection, preservation, and use of DNA evidence.  Fundamental knowledge of the capabilities of DNA technology is essential for police officers to collect evidence properly, prosecutors and defense attorneys to introduce and use it successfully in court, and judges to rule correctly on its admissibility.  Victim service providers and medical personnel likewise need to understand DNA technology in order to encourage more successful evidence collection and to be fully responsive to the needs of victims.

Law Enforcement Training

        As the first responders to crime scenes, law enforcement officers should be able to identify, collect and preserve probative biological evidence for submission to crime laboratories.  Improper collection can mean that valuable evidence is missed or rendered unsuitable for testing.  The initiative devotes $3.5 million in FY 2004 to assist law enforcement in meeting the following training needs:   

  • Basic “awareness training” on DNA evidence for patrol officers and other first-responders; 
     
  • Intensive training on identifying, collecting, and preserving potential DNA evidence for evidence technicians, investigators, and others processing crime scenes;  
     
  • Training and education for investigators and responding officers on DNA databases and their potential to provide leads in current and “cold” cases; and
     
  •  Training and information for law enforcement leadership and policymakers to facilitate more informed decisions about effective DNA evidence collection and testing.

Training Prosecutors, Defense Attorneys, and Judges

        In order to achieve just results in cases involving DNA evidence, prosecutors, defense attorneys, and judges should receive proper training on the use and presentation of DNA evidence.  The initiative devotes $2.5 million in FY 2004 to support:

 

  • Training and technical assistance for prosecutors to learn about solving “cold cases” with DNA evidence, responding to post-conviction DNA testing requests, and developing innovative legal strategies to optimize the power of forensic DNA technology.  Grant funds will be available for state and local prosecutors’ organizations for the development and delivery of training materials to assist prosecutors in presenting this evidence before courts and juries, and in understanding more about the value of DNA evidence in particular cases. 
     
  • Training for defense counsel handling cases involving biological evidence on the applications and limitations of DNA evidence.  Grant funds will be made available to continuing legal education programs or bar associations to provide training and resources on forensic DNA technology.
     
  • Training for judges, who must be equipped with sufficient technical and scientific knowledge to make appropriate rulings in cases involving DNA evidence.  Grant funds will be available to national judicial conferences and organizations.
     

Training For Probation and Parole Officers and Corrections Personnel

        Probation and parole officers play a critical role in ensuring that offenders are complying with their statutory obligations to provide DNA samples.  Corrections personnel often are responsible for obtaining DNA samples from inmates required by law to submit such samples.  Through training and education programs, these professionals will be better equipped to ensure that samples are taken from all individuals who are required by law to provide them.  The initiative calls for $1 million in FY 2004 to support this training.

Training for Forensic Scientists

        The forensic science community has a critical need for trained forensic scientists in public crime laboratories.  The initiative will assist the development of comprehensive training programs for a new generation of forensic scientists, enabling new forensic scientists to receive in-depth training to prepare them for analyzing actual casework in a crime laboratory.  The initiative calls for $3 million in FY 2004 to support this training.

Training for Medical Personnel

The initiative will also provide $5 million in FY 2004 to support the development of training and educational materials for doctors and nurses involved in treating victims of sexual assault.  Trained medical personnel are needed to effectively collect usable DNA evidence, while safeguarding the privacy rights and addressing the needs of rape victims requiring sexual assault exams.  These programs will specifically target underserved areas of the country.  Funding may also be used to support the development of SANE (Sexual Assault Nurse Examiner), SAFE (Sexual Assault Forensic Examiner), and SART (Sexual Assault Response Team) programs. 

Training for Victim Service Providers

Victims and those who advocate on their behalf must have access to information about the investigative and courtroom uses of forensic DNA evidence. Victims should be properly informed about how DNA evidence may impact their cases.  In situations involving post-conviction DNA testing, victim service providers must be able to assist victims through the often-painful process of newly-ordered DNA tests and re-opened court proceedings.  To address the concerns of victims, the initiative would develop additional DNA education and training programs for victim advocates and victim service providers so that they may better assist victims in all cases involving DNA evidence.  The initiative calls for $5 million in FY 2004 to support this training.

TOC | Executive Summary | Using DNA to Protect the Innocent

Updated March 7, 2017