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Untested Evidence in Sexual Assault Cases

NCJ Number
Date Published
March 2016
6 pages

After reviewing the widespread problem among U.S. law enforcement agencies of backlogs of sexual assault kits (SAKs) that have not been submitted to crime laboratories for testing, this paper reviews the methodology and findings of action-research projects in Detroit, MI, and Houston, TX, intended to find solutions to this problem.


An overview of this problem focuses on reasons for the prevalence of SAK backlogs. In 2011, NIJ awarded action-research grants to the Houston Police Department and the Detroit Prosecutor's Office. Both sites formed multidisciplinary teams to examine the SAK backlogs and then develop effective, sustainable responses for addressing the problem. One of the most important findings from both jurisdictions is the value of forming multidisciplinary teams to address the issue. This paper also reports on a NIJ-funded study in Los Angeles, which examined the role of DNA testing of SAKs in the backlog. This study assessed the efficacy of DNA testing and determined the criminal justice outcomes from testing SAKs in the backlog (arrest, charge, convictions) within the first 6 months after the kits were tested for DNA. The study unexpectedly found that in the first 6 months after testing 371 SAKs, no new arrests were made; new charges were filed in only one case, and there were two convictions. Further, it is probable that the DNA testing was not responsible for the single filing or the two convictions. A similar study in New Orleans is also summarized. This paper provides online access to reports on these projects.

Date Published: March 1, 2016