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Press Release

Former Los Alamos National Laboratory Worker Sentenced for Violating Atomic Energy Act Violations

For Immediate Release
U.S. Attorney's Office, District of New Mexico

ALBUQUERQUE – The Justice Department today announced that a former contract employee at the Los Alamos National Laboratory (LANL) was sentenced this morning for conspiring to violate the Atomic Energy Act by communicating classified nuclear weapons data to a person believed to be a Venezuelan government official, and making false statements to the FBI.

Marjorie Roxby Mascheroni, 71, of Los Alamos, N.M., was sentenced by U.S. District Judge William P. Johnson to a year and a day in federal prison followed by three years of supervised release based on a guilty plea entered in June 2013.  Her husband, Pedro Leonardo Mascheroni, 79, a naturalized U.S. citizen from Argentina who is also a former LANL employee, also entered a guilty plea in June 2013, and is in federal custody pending his sentencing hearing.

According to court filings, Mascheroni, a Ph.D. physicist, worked as a scientist at LANL from 1979 to 1988 and held a security clearance that allowed him access to certain classified information, including “Restricted Data.”  Roxby Mascheroni worked at LANL between 1981 and 2010, where her duties included technical writing and editing.  She also held a security clearance at LANL that allowed her access to certain classified information, including “Restricted Data.”  As defined under the Atomic Energy Act, “Restricted Data” is classified information concerning the design, manufacture or use of atomic weapons; the production of special nuclear material; or the use of special nuclear material in the production of energy.

Mascheroni and Roxby Mascheroni were indicted in Sept. 2010, and charged with conspiracy to communicate and communicating Restricted Data to an individual with the intent to secure an advantage to a foreign nation.  The indictment also charged the couple with conspiracy to convey and conveying classified Restricted Data.  It also charged Mascheroni with concealing and retaining U.S. records with the intent to convert them to his own use and gain, and both defendants with making false statements.

Roxby Mascheroni pled guilty to Count 6 of the indictment, charging her with conspiracy, and Counts 16 through 22, charging her with making false statements.  She also pleaded guilty to an information charging her with conspiracy to communicate Restricted Data.  In entering her guilty plea, Roxby Mascheroni admitted that between Oct. 2007 and Oct. 2009, she conspired with Mascheroni to convey Restricted Data belonging to the United States to another person with reason to believe that the information would be used to secure an advantage to Venezuela. She also admitted making materially false statements to the FBI when she was interviewed in Oct. 2009.

Mascheroni pleaded guilty to Counts 7 and 8 of the indictment, charging him with conversion of government property, and Counts 10 through 15, charging him with making false statements.  Mascheroni also pleaded guilty to an information charging him with two counts of communication of Restricted Data and one count of retention of national defense information.  Mascheroni admitted that in Nov. 2008 and July 2009, he unlawfully communicated Restricted Data to another individual with reason to believe that the data would be utilized to secure an advantage to Venezuela.  He also admitted unlawfully converting Department of Energy information to his own use and selling the information in Nov. 2008 and July 2009, and failing to deliver classified information relating to the United States’ national defense to appropriate authorities and instead unlawfully retaining the information in his home.  Finally, Mascheroni admitted making materially false statements to the FBI when he was interviewed in Oct. 2009. 

The indictment in this case did not allege that the government of Venezuela or anyone acting on its behalf sought or was passed any classified information, nor did it charge any Venezuelan government officials or anyone acting on their behalf with wrongdoing.  The indictment also did not allege any wrongdoing by other individuals working at LANL.

This investigation was conducted by the FBI’s Albuquerque Division with assistance from the Department of Energy and LANL.  The prosecution is being handled by Assistant U.S. Attorneys Fred J. Federici, Dean Tuckman and Holland S. Kastrin of the U.S. Attorney’s Office for the District of New Mexico, and Acting Section Chief Kathleen Kedian and Trial Attorney David Recker of the Counterespionage Section of the Justice Department’s National Security Division.

Updated January 26, 2015