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Understanding DNA Evidence: A Guide for Victim Service Providers

About This Bulletin

Stories about the use of DNA evidence to convict offenders or exonerate defendants in criminal cases have appeared in the media with increasing frequency over the last few years. Criminal justice professionals and the public realize that forensic DNA technology is revolutionizing the way law enforcement officers investigate violent crimes, including crime scene investigation, counseling rape victims to not wash away critical evidence, accurate conviction of offenders, and connecting offenders to other brutal crimes. This bulletin seeks to strengthen crime victims' confidence in the judicial process by showing how DNA technology can empower the search for truth.

The importance of DNA evidence has grown considerably in recent years as improved technology renders more accurate results and DNA evidence is used more frequently to convict or exonerate defendants. As a result of its awesome ability to convict a perpetrator or exonerate a convicted offender, particularly in sexual assault and homicide cases, DNA evidence has become a powerful crimefighting tool.This is precisely why victim service providers need to know the significance of DNA evidence in victims' cases. They also should understand how the identification, collection, and preservation of DNA at the crime scene is critical in obtaining accurate test results.

Victims need to be provided with a simple but thorough explanation of how DNA testing may be used in their case, the process and procedures used, and the potential outcomes of the test results. It is important that victim service providers relay this information to victims early in the investigative process to help victims understand how DNA is used in investigating crimes and how it can improve the chances of apprehending and convicting an offender.

DNA evidence is a useful and neutral tool in the search for justice. Whether it helps convict or absolve individuals, DNA evidence will play an increasingly important role in solving crimes in the future. The result will be better justice for victims and safer communities.

Understanding DNA Evidence: A Guide for Victim Service Providers
by Kathryn M.Turman


What Is DNA?

The Value of DNA Evidence

Evidence Collection and Preservation

Contamination Issues

Forensic DNA Testing

DNA Testing Methods

Interpreting Results of DNA Analysis

DNA Evidence: Closed Cases and Unsolved Cases

Using CODIS To Solve Crimes

Case Studies: The Power of a DNA Match

Postconviction DNA Testing




For Further Information

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Kathryn McKay Turman joined the Office for Victims of Crime in July 1998. She served as 1 of 22 Commissioners appointed to the National Commission on the Future of DNA Evidence. From 1994 to 1998, she was Chief of the Victim Witness Assistance Unit in the U.S. Attorney's Office for the District of Columbia. As head of that unit, she oversaw services to about 10,000 victims a year, ranging from victims of misdemeanor crimes to international terrorism. From 1991 to 1993, she served as Director of the Justice Department's Missing and Exploited Children's Program. Prior to joining the U.S. Department of Justice in 1991, she was Special Assistant to the late U.S. Senator John Heinz. She is a social worker and a graduate of the University of Texas at Austin. She gives special thanks and recognition to Chris Asplen and Dr. Lisa Forman, both of the National Commission on the Future of DNA Evidence, lead writer/editor Theodosia Craig, and contributing writer/editor Nancy Walsh.

Preparation of this document was supported by the Office for Victims of Crime,Office of Justice Programs, U.S. Department of Justice. The opinions,findings, conclusions,and recommendations expressed in this document are those of the author and do not necessarily represent the official position or policies of the U.S. Department of Justice.

The Office for Victims of Crime is a component of the Office of Justice Programs, which also includes the Bureau of Justice Assistance, the Bureau of Justice Statistics, the National Institute of Justice,and the Office of Juvenile Justice and Delinquency Prevention.

April 2001

NCJ 185690

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