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About Backlogs and Untested Kits

DNA evidence often plays a key role in successful sexual assault prosecutions. Sexual assault victims who report the crime to law enforcement are usually asked to submit to a medical forensic exam that includes collecting DNA evidence. That evidence is preserved in a sexual assault kit (also called a “rape kit”), and entered into police evidence.  

Backlogged vs. Untested Kits

Although the term “backlog” is often used by the media, general public, and others to describe the nationwide problem of sexual assault kits, there are actually two distinct concepts at play when discussing the issue of rape kits that have not been tested expeditiously: backlogged kits and untested kits.

  • Backlogged kits refer to the untested evidence submitted to laboratory facilities.
  • Untested kits remain in law enforcement custody, and have not be sent to the lab for analysis

Although there is no industry-wide standard, the National Institute of Justice defines a backlogged kit as one that has been at the lab for at least 30 days.[1] Backlogs in some labs can be as long as 5 years.[2]

Untested kits may have been sitting on shelves and in storages facilities in law enforcement custody—some of these kits may date as far back as the 1980s.  

Why is there a lab backlog?

Reasons for the backlog at crime labs vary. In most cases, the demand is just too high for the labs to keep up with incoming testing requests. As DNA evidence is collected in more criminal cases, the volume of DNA testing has increased dramatically, making it difficult for laboratories to keep up with the demand. With this high volume of evidence—which is sometimes prioritized due to circumstances such as a serial killer or rapist operating in a locality—rape kits sometimes end up at the bottom of the queue.  Regardless of the reasons for the backlog, untested rape kits leave crimes unsolved, offenders free, and victims without justice.

Why are there untested sexual assault kits in law enforcement custody?

 In most jurisdictions, there are no laws requiring the testing of sexual assault kits (SAKs). In general, SAKs are not tested unless testing is specifically requested by a law enforcement agency for a criminal investigation.  There are a variety of reasons that a kit might not be tested, including: 

  • A decision by law enforcement due to a various reasons, such as prioritization of sexual assault cases and perceived victim credibility or cooperation, not to further investigate the case.
  • A decision by law enforcement that the results of the kit would not be significant to the investigation. This occurs most often when the suspect does not deny physical contact, but instead claims the contact was consensual.
  • A jurisdiction may lack understanding about the nature of sexual assault and perpetuators and keep kits in storage based on misinformation and myth.
  • Lack of funding for DNA analysis. Some law enforcement jurisdictions, including crime laboratories, are underfunded and may be unable to test every SAK. 

Legislative History

The problem of backlogged and untested rape kits has been evident for more than a decade. In 1999, New York City reported having 17,000 backlogged rape kits. In 2004, the U.S. Department of Justice estimated a backlog of hundreds of thousands of untested DNA samples in state or local crime labs and evidence warehouses throughout the United States. That year, President Bush proposed $232.6 million in funding for the Advancing Justice Through DNA Technology initiative. Congress authorized the appropriation—through the Justice for All Act—of $151 million each year for fiscal years 2005–2009 for state and local governments to conduct analyses of backlogged DNA samples collected from victims and criminal offenders.

The legislation (reauthorized in 2008), led to significant increases in testing; however, many thousands of kits remain untested every year. In 2009, the Bureau of Justice Statistics reported a year-end backlog of more than 100,000 kits. Although the numbers continue to fluctuate, the problem persists.

Training and Technical Assistance

As communities work toward reducing backlogged and untested sexual assault kits, they should sensitively support victims and knowledgeably address their rights and needs. The National Center for Victims of Crime’s DNA Resource Center is available to provide training, technical assistance, and resources to ensure victim-centered responses to the problem of backlogged and untested sexual assault kits.

To request technical assistance, please contact Ilse Knecht, Deputy Director of Public Policy, atIKnecht@ncvc.org or 646-620-5270.



[1] Mark Nelson, Making sense of DNA Backlogs—Myth versus reality, NIJ Journal 226: 20-25 (May 2010), http://www.nij.gov/journals/266/Pages/backlogs.aspx.

[2] http://www.memphisflyer.com/NewsBlog/archives/2014/02/12/memphis-needs-55-million-5-years-to-clear-rape-kit-backlog


This project is supported by Grant No. 2011-TA-AX-K048 awarded by the Office on Violence Against Women, U.S. Department of Justice. The opinions, findings, conclusions, and recommendations expressed in this program are those of the author(s) and do not necessarily reflect the views of the Department of Justice, Office on Violence Against Women.