Unrealized Potential of DNA Testing, Research in Brief

The development of forensic DNA testing has expanded the types of useful biological evidence. Substances such as saliva, teeth, and bones, as well as semen and blood, can be sources of DNA. These sources are expanding still further, as researchers explore the potential of other biological substances such as hair, skin, cells, and fingerprints. However, the use of DNA evidence is currently limited because much of what could be tested remains unrecovered and unanalyzed. Samples have been obtained from less than half the individuals convicted for sexual assault for whom DNA collection is legislatively mandated and only 20 percent of the DNA samples obtained have been processed. The reasons for the lag in evidence recovery and processing are the scarcity of law enforcement resources, laboratory backlogs caused by insufficient funding, and time-consuming and costly testing methods. It is impossible to analyze all the potential evidentiary specimens submitted under the deadlines imposed by the courts. Improvements in technology to speed the processing of DNA evidence should make it possible to overcome these obstacles within the next few years. In addition, the development of DNA databases and networks can substantially augment DNA profiling. Finally, the initial collection of evidence is improving as a result of the establishment in many jurisdictions of more structured crime-scene teams and more formalized evidence collection procedures. Illustrations and reference notes