in one or more of the following disciplines: controlled substances, trace, biology (including DNA), toxicology, latent prints, questioned documents, firearms/toolmarks, or crime scene.”4 More recently, increasing numbers of laboratories specialize in the analysis of evidence in one area, for example, DNA or digital evidence. (See Chapter 5 for a more complete description and discussion of the forensic science disciplines.)

The capacity and quality of the current forensic science system have been the focus of increasing attention by Congress, the courts, and the media. New doubts about the accuracy of some forensic science practices have intensified with the growing number of exonerations resulting from DNA analysis (and the concomitant realization that guilty parties sometimes walk free). Greater expectations for precise forensic science evidence raised by DNA testing have forced new scrutiny on other forensic techniques. Emerging scientific advances that could benefit forensic investigation elicit concerns about resources, training, and capacity for implementing new techniques. A crisis in backlogged cases, caused by crime laboratories lacking sufficient resources and qualified personnel, raises concerns about the effectiveness and efficiency of the criminal justice system. When backlogs prolong testing time, issues involving speedy trials may arise. In addition, backlogs discourage law enforcement personnel and organizations from submitting evidence. Laboratories also may restrict submissions of evidence to reduce backlogs. All of these concerns, and more, provide the background against which this report is set.

Finally, if evidence and laboratory tests are mishandled or improperly analyzed; if the scientific evidence carries a false sense of significance; or if there is bias, incompetence, or a lack of adequate internal controls for the evidence introduced by the forensic scientists and their laboratories, the jury or court can be misled, and this could lead to wrongful conviction or exoneration. If juries lose confidence in the reliability of forensic testimony, valid evidence might be discounted, and some innocent persons might be convicted or guilty individuals acquitted.

Recent years have seen a number of concerted efforts by forensic science organizations to strengthen the foundations of many areas of testimony. However, substantial improvement is necessary in the forensic science disciplines to enhance law enforcement’s ability to identify those who have or have not committed a crime and to prevent the criminal justice system from erroneously convicting or exonerating the persons who come before it.


Ibid., p. 24.

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