By Phil Bulman, Writer/Editor, National Institute of Justice, Washington, D.C.
any police departments in the United States collect DNA evidence only in violent crime cases. Historically, investigators believed that it would be too expensive to collect biological evidence and perform DNA analysis in burglaries and other high-volume property crimes.
However, the cost of doing DNA analyses is decreasing. The amount of data in state and national DNA databases is increasing, and databases include a growing number of profiles of both violent and nonviolent felons. Based on information in these databases—and other information about criminal careers—researchers have found that many property offenders do not “specialize.” Many also commit violent crimes and drug crimes.
For example, a Florida study revealed that 52 percent of DNA database hits against murder and sexual assault cases matched people who were originally put in the database for burglary convictions.1
Criminal justice experts have long known that property crime offenders have highrecidivism rates. The types of crimes they perpetrate, including the level of violence, can escalate. Property crime cases frequently go unsolved. The Federal Bureau of Investigation reported that the average property loss from a burglary was $2,096 in 2009.2 Burglars are often high-rate offenders and the total cost from their crimes may be many times this amount. Consequently, using DNA to identify and arrest burglars who otherwise would not be brought to justice can prevent a variety of crimes.
In the past, the use of DNA to solve property crimes seemed like a poor investment, particularly if only the cost of a single crime was considered. However, when the United Kingdom reported success in using DNA to solve property crimes, NIJ funded a field experiment to look beyond the single property offense to the possible arrest of a high-rate offender. NIJ funding supported the purchase of supplies and equipment, as well as expenses of additional law enforcement personnel, prosecutors, crime laboratory personnel, and outside DNA analysis services.
The results of the study challenge the belief that collecting and analyzing DNA evidence in property crimes is cost prohibitive. The study shows using DNA in property crimes is cost effective and dramatically increases the numbers of burglary suspects identified. The results suggest that DNA collected from a property crime scene has not only the potential to prevent future burglaries, but more serious violent offenders can be brought to justice, leading to safer communities.
Testing the Use of DNA to Solve Property Crimes in the Field
NIJ-funded research teams conducted a five-city field study that evaluated the effectiveness of analyzing biological evidence collected from property crime scenes.
Local law enforcement agencies, crime labs, and prosecutors collaborated in the project, which was called the DNA Field Experiment. The participating communities included Los Angeles, California; Topeka, Kansas; Denver, Colorado; Phoenix, Arizona; and Orange County (Calif.). The study focuses on whether it is cost effective to use DNA testing to investigate ordinary property crimes.
Several interesting factors doubled when researchers tallied the results.
When compared to a traditional property crime investigation that focused on fingerprints, investigators identified and arrested twice as many suspects when DNA evidence was collected. Prosecutors accepted twice as many cases for processing when DNA was part of the evidence. The people arrested had twice as many previous arrests, on average, and twice as many prior convictions when compared to those arrested based on traditional investigations. Moreover, DNA was twice as effective in identifying suspects as were fingerprints. In cases where investigators collected both fingerprint and biological evidence, analysts got twice as many hits using the FBI’s Combined DNA Index System (CODIS) than in the Integrated Automated Fingerprint Identification System (IAFIS).
Due to differences among the five jurisdictions, outcomes varied, sometimes substantially. However, the study of the five sites produced these interesting findings in common:
- DNA samples collected by patrol officers were no less likely to yield good evidence than those collected by forensic technicians.
- Among the cases in which biological evidence was collected, fingerprint evidence was collected in one-third of the cases.
- The larger the state DNA database (percentage of state population), the more likely that an identification was made; this trend was revealed when comparing across sites and over the course of the study as California rapidly expanded its database.
In the future, collecting DNA at property crime scenes may yield even better results as the size of the databases grows.
What should state and local jurisdictions look at when considering whether to adopt a policy for using DNA to solve property crimes?
Perhaps one of the most important lessons learned from the NIJ field experiment was the following: a high level of collaboration between city police, county prosecutors, and county and state crime labs is required to be successful. In the field experiment, as collaboration increased—fostered through biweekly conference calls, sitevisits, and semiannual workshops—data systems and investigative processes improved.
Indeed, producing the most cost-effective results in the use of DNA to solve property crimes requires collaboration across multiple laboratory, and the prosecutor’s office.
To learn more, visit www.nij.gov. Read the original research by John Roman et al., The DNA Field Experiment: Cost-Effectiveness Analysis of the Use of DNA in the Investigation of High-Volume Crimes, final report submitted to the National Institute of Justice, which is available at www.ncjrs.gov/pdffiles1/nij/grants/222318.pdf.♦
1Florida Department of Law Enforcement, State DNA Database Statistics, Tallahassee, Florida.
2U.S. Department of Justice, Federal Bureau of Investigation, Criminal Justice Information Services, Uniform Crime Report, Crime in the United States, 2009, www2.fbi.gov/ucr/cius2009/index.html (accessed March 11, 2013).
Please cite as:
Phil Bulman, "DNA and Property Crimes," Research in Brief, The Police Chief 80 (April 2013): 16–17.