Nationwide, 14 percent of open homicide cases and 18 percent of open rape cases contain forensic evidence that has not been sent to a crime lab for analysis, says a survey commissioned by the Justice Department’s National Institute of Justice. The survey of more than 2,000 state and local police agencies found significant disparities regarding computerized evidence-tracking capabilities and evidence-retention policies.
A law enforcement agency may not submit forensic evidence to a lab if it is considered not probative, charges may have been dropped or a guilty plea entered. Still, researchers who conducted the survey said some law enforcement agencies may not fully understand the value of evidence in developing new investigative leads. The survey found that only four out of 10 law enforcement agencies have a computerized system for tracking forensic evidence either in their inventory or after it is sent to the crime lab.