A DNA match –a crime “solved” by the FBI’s database – does not mean there was an arrest, a prosecution, or even that detectives considered a case closed, says USA Today. How many DNA matches lead to an arrest isn’t known. A USA Today investigation found almost three dozen cases in the past five years – including a rape in Virginia – in which investigators failed to pursue potential suspects whose DNA matched evidence found at crime scenes. DNA matches that could have closed cases weren’t pursued because of basic police foul-ups, such as overlooking a telephone message reporting the match. Backlogs of unsolved “cold cases” that threaten to overwhelm some big-city police departments caused matches to be ignored.
The FBI DNA database is called CODIS, for Combined DNA Index System. It has cost the government hundreds of millions of dollars to build and has proved adept at making matches in “cold cases” in which police had no leads and little hope of finding a suspect. Its dozens of successes include clearing innocent suspects, bringing rapists to justice 30 years after their offenses, and linking burglars to murders, rapes and other violent crimes in which they never were suspects. The FBI says it is unfair to hold CODIS accountable for what happens to the “investigative leads” after they are furnished to investigators.