Should DNA testing in police investigations be routine? : The Campbell Collaboration

Does the use of DNA testing improve case outcomes? The findings of a recent Campbell systematic review indicate that DNA testing should be used in routine police investigations.

The findings from a Campbell systematic review suggest that DNA testing is a valuable tool in investigating a variety of crimes. Instead of using DNA analysis simply to corroborate the guilt (or innocence) of a previously identified suspect, DNA databases can themselves identify suspects before there is any other evidence implicating the individual. Incorporating DNA testing into routine police investigation both improves case outcomes, but also builds up DNA databases. It can be argued that as the size of a DNA database expands, the effectiveness of DNA testing on a broad scale will increase.

DNA testing under which circumstances?
The evidence supporting DNA testing for property crimes was consistent across the included studies. The support for the value of DNA in more serious crimes is generally positive but based on weak evidence.

What kind of further research is needed?
Additional studies are needed, particularly those using randomized experimental designs, in order to support the generalizability of these findings.

The review team was led by Dr David B. Wilson, Professor & Chair of the Department of Criminology, Law & Society at George Mason University.

Read the report