in the forensic science disciplines and related areas of inquiry. Thus, in this report, the term “forensic science” is used with regard to a broad array of activities, with the recognition that some of these activities might not have a well-developed research base, are not informed by scientific knowledge, or are not developed within the culture of science.


As mentioned above, a number of factors have combined in the past few decades to place increasing demands on an already overtaxed, inconsistent, and underresourced forensic science infrastructure. These factors have not only stressed the system’s capacity, but also have raised serious questions and concerns about the validity and reliability of some forensic methods and techniques and how forensic evidence is reported to juries and courts.

The Case Backlog—Insufficient Resources

According to the 2005 BJS census report, a typical publicly funded crime laboratory ended the year with a backlog of about 401 requests for services, received another 4,328 such requests, and completed 3,980 of them. Roughly half of all requests were in the area of controlled substances. The average backlog has risen since the 2002 census,6 with nearly 20 percent of all requests backlogged by year end. The Department of Justice (DOJ) defines a case as backlogged if it remains in the laboratory 30 days or more without the development of a report or analysis. Federal, state, and local laboratories reported a combined backlog of 435,879 requests for forensic analysis.7 According to the census, a typical laboratory performing DNA testing in 2005 started the year with a backlog of 86 requests, received 337 new requests, completed 265 requests, and finished the year with 152 backlogged requests.

The backlog is exacerbated further by increased requests for quick laboratory results by law enforcement and prosecutors. Witnesses before the committee testified that prosecutors increasingly rely on laboratories to provide results prior to approving charges and have increased requests for additional work on the back end of a case, just before trial.8 Backlogs are compounded by rising police agency requests for testing (e.g., for DNA evidence found on guns and from nonviolent crime scenes). Laboratories


J.L. Peterson and M.J. Hickman. 2005. Census of Publicly Funded Forensic Crime Laboratories, 2002. U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics. Available at


Durose, op. cit.


J.L. Johnson, Laboratory Director, Illinois State Police, Forensic Science Center at Chicago. Presentation to the committee. January 25, 2007.

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