The Denver Police Department has acknowledged that it destroyed all evidence, including items that could have yielded DNA, in 90 percent of sexual-assault cases before 1995, the Denver Post reports. The department made the disclosure in a grant application seeking funds to reduce a backlog of items needing DNA analysis. The application does not say what kind of evidence was destroyed or how many cases are involved, though it notes that the department investigated 480 sexual assaults each year in the 1990s. Police Chief Gerry Whitman said that prior to 1995, evidence was destroyed on an ongoing basis because, at the time, the department was unable to do DNA testing on all evidence.
Whitman said the department did not start DNA analysis until 1994 and did not first analyze most of the evidence that was destroyed to see whether it could have yielded DNA. DNA was first introduced in U.S. courtrooms in 1987, and the Federal Bureau of Investigation launched a program in 1990 to create a national databank of DNA specimens collected from crime scenes and taken from convicted felons. Nationally, no uniform regulations govern police departments’ DNA preservation, leaving most agencies with broad discretion to purge items that might hold blood, saliva, and semen. While some departments, such as Dallas, have kept DNA from felony cases since before the DNA revolution in the mid-1980s, others such as Los Angeles have destroyed evidence, scuttling efforts to solve cases. Los Angeles has since changed its procedures to keep DNA permanently. Whitman said the Denver department destroyed the evidence because of space limitations.