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TOC | Using DNA to Solve Crimes | Using DNA to Identify Missing Persons


        DNA technology is increasingly vital to ensuring fairness in the criminal justice system.  Every effort that is made to reduce backlogs of untested evidence, to better equip forensic laboratories, to develop faster methods of analyzing samples, and to better train professionals in the use of DNA technology, will improve the accuracy of the criminal justice system.  Accordingly, the measures described in the previous sections will not only help solve crimes and keep dangerous offenders off the streets, but will also help minimize the risk that innocent individuals are wrongly accused or convicted. 

        Post-conviction DNA testing has received considerable attention in recent years.  Since the advent of forensic DNA analysis, a number of individuals convicted of crimes have been subsequently exonerated through DNA analysis of crime scene evidence that was not tested at the time of trial.  The following are two recent reported examples:

  • In February 2003, a Hampton Roads, Virginia man was released from prison after post-conviction DNA tests proved that he did not rape a nursing student in 1981.  The man had spent two decades in prison after being convicted of breaking into the woman’s apartment and raping her.  Two juries failed to reach a verdict, but a third jury found him guilty. From the time of his arrest, however, the man maintained his innocence.  Last year, a Virginia crime lab located evidence in the man’s case in a file maintained by a forensic scientist who had since died.  DNA tests conducted on this evidence proved that he was not the perpetrator, and have preliminarily linked the crime scene evidence to a felon whose DNA sample was maintained in the Virginia DNA database.  The Norfolk Commonwealth Attorney supported the man’s immediate release from prison after learning of the DNA test result. Law enforcement authorities are following up on the “cold hit.” 
  • A Maryland man served 20 years of a 30-year sentence after being convicted of a 1982 home invasion rape of a schoolteacher.  Through post-conviction DNA testing, the man was exonerated in 2002.  When the crime scene profile was uploaded to CODIS, it was preliminarily linked to a felon whose DNA profile was maintained in a DNA database. This man has subsequently been arrested and charged for the 1982 crime, and is awaiting trial later this year.  The original defendant was pardoned in January 2003.

        Many states have already enacted provisions that allow convicted offenders in certain cases to seek post-conviction DNA testing of evidence collected in those cases.  Currently, 31 states have enacted special statutory provisions providing post-conviction DNA testing, and additional states make post-conviction testing available through other procedures.  Federal law also should provide for post-conviction DNA testing in appropriate cases. 

        To demonstrate support for appropriate post-conviction testing of DNA evidence, the Attorney General will create a $5 million grant program under the President’s initiative to help states defray the costs of post-conviction DNA testing.  In order to receive this funding, state programs will be required to meet criteria established by the Department of Justice.  These criteria will require that DNA testing be performed by an accredited forensic laboratory, and will encourage states to develop plans that ensure prompt DNA testing of persons who may be wrongly convicted and discourage frivolous testing that may cause unnecessary expense and needless harm to crime victims. 

TOC | Using DNA to Solve Crimes | Using DNA to Identify Missing Persons

Updated March 7, 2017