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
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.
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.
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.
Date Modified: February 16, 2011