DNA Evidence Backlogs: Forensic Casework

Describing the Forensic Casework Backlog

Forensic evidence is collected from crime scenes, victims and suspects in criminal cases and then submitted to a laboratory. Processing this evidence is time-consuming because it must first be screened to determine whether any biological material is present and, if so, what kind of biological material it is. Only then can DNA testing begin. In addition, some samples can be degraded or fragmented or may contain DNA from multiple suspects and victims.

Counting the Forensic Casework Backlog

The number of backlogged cases in crime laboratories changes daily. New DNA evidence is submitted, and older DNA cases are closed every day. Because the number is constantly changing, estimates of the number of backlogged cases nationwide is always fluid.

The most current nationwide assessment of the DNA casework sample backlog was provided to NIJ by state and local units of government who applied for funding under the fiscal year 2010 Forensic DNA Backlog Reduction Program. The data they provided points to a national backlog of 100,628 DNA cases as of January 1, 2009, which grew to 111,647 by the end of the year. By contrast, a study by the Bureau of Justice Statistics pointed to a nationwide backlog of 24,030 DNA cases on January 1, 2005, which grew to 38,227 by the end of that year.[1]

Addressing the Forensic Casework Backlog

Federal funding has contributed to the significant progress made toward clearing old cases from crime laboratories. Today's casework backlog consists of recent cases, not older ones; the backlogged cases from 2004, when Congress passed the DNA Initiative legislation, are gone. However, backlogs continue to be a problem in many laboratories because demand for DNA testing services is increasing faster than the capacity of laboratories to process cases.

DNA Casework Trends: Supply, Demand, Backlogs
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Consider the data in the figure "DNA Casework Trends: Supply, Demand, Backlogs," and the story they tell about crime laboratory backlogs. The "new cases" data show the tremendous growth in demand for DNA testing (i.e., casework) between 2005 and 2009. The capacity of laboratories to complete cases grew at about the same rate as new cases were submitted, as shown by the "completed cases" data. But the number of new cases submitted grew faster than did the capacity to process the new and present workload, hence, a backlog.

The bottom line: Crime laboratories have increased their capacity to work cases significantly, but they are not able to eliminate their backlogs because the demand continues to exceed the increases made in capacity.

[1] Census of Publicly Funded Forensic Crime Laboratories, 2005, Washington, DC: Bureau of Justice Statistics, U.S. Department of Justice, July 2008, NCJ 222181.

Date Modified: February 16, 2011