Law & the Genetics of Identity: The Science of DNA Fingerprinting

PRODUCERS: Larry Massett

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New & Noteworthy, 2007
by Jennifer Jongsma

In Law and The Genetics of Identity, The DNA Files looked at DNA forensics, privacy and the law. There are many ways in which experts use genetic techniques for identification purposes, from identifying missing persons to solving criminal investigations. DNA evidence arguably has become the best-known type of forensic evidence, made more recognizable by popular television programs (including three CSIs and four Law & Orders). Although the forensic tools used on TV allow detectives to solve horrendous crimes in under an hour, real-life techniques do require a few days.

A DNA profile is a composite of about 13 areas of highly variable short tandem repeats (STRs) that characterize each individual. While humans share a vast majority of our DNA sequence with one another, some sections of our non-coding DNA are unique. Using DNA profiling techniques, it is possible to establish a likely match.

The International Commission on Missing Persons (ICMP) was created in 1996 as a result of the conflicts related to Bosnia-Herzegovina, the Republic of Croatia, and Republic of Serbia from 1991 to 1995. The ICMP uses DNA as a means to identify victims of war atrocities and natural disasters. As of April 2006, the ICMP had helped identify 902 people who had died in the 2004 South Asian tsunami. In 2005, the ICMP partnered with Louisiana health officials to perform DNA tests on 256 bone samples from Katrina victims. Forensic specialists created DNA profiles from these bone samples then sent the data to Louisiana authorities for matching with family members' DNA samples there.

In recent years, researchers and policing organizations also have made significant inroads in criminal investigation methods. New forensic polymerase chain reaction (PCR), STR, and mtDNA techniques have sped up analysis of a DNA profile extracted from crime scene evidence. What once took between 6 and 8 weeks now takes between 1 and 2 days. Scientists hope that someday it will take only a few hours to generate a DNA profile from a sample. According to President George W. Bush's DNA Initiative in 2003, "one of the biggest problems facing the criminal justice system today is the substantial backlog of unanalyzed DNA samples and biological evidence from crime scenes, especially in sexual assault and murder cases." Timely analysis of these samples can help police arrest and detain potentially violent offenders or solve "no-suspect" cases. While timely analysis is important, identifying the correct person is even more important. Opponents of DNA profiling point out that case-specific issues and problems often damage the quality and relevance of DNA test results.

The increased use of genetic technologies in crime investigation has contributed to many forensic databases, including two run by the Federal Bureau of Investigation: the Automated Fingerprint Identification System, which catalogs millions of fingerprints, and the Combined DNA Index System (CODIS). CODIS was once reserved for those convicted of violent offenses, but the 2004 Justice for All Act expanded the database so states can now upload profiles of almost anyone charged with any crime. In 2006, the FBI opened its DNA database to kinship DNA matching. A DNA sample from a crime scene that fails to be an exact match to any profile in a forensic database can now be used to find possible relatives that are in the database. Opponents fear that partial matches violate protection by the U.S. Constitution against unreasonable search and seizure and undermine the principle of presumptive innocence.

Genetic techniques can also be used to exonerate a person convicted of a crime. As of October 2007, the Innocence Project, founded by Barry C. Scheck and Peter J. Neufeld at the Benjamin N. Cardozo School of Law at Yeshiva University in New York, had helped exonerate 208 people in the United States using DNA testing, including 15 who served time on death row. Byron Halsey, for instance, who narrowly escaped the death penalty when he was convicted in 1988 of the brutal sexual assault and murder of two young children in New Jersey, was fully exonerated in July 2007 based on DNA evidence. DNA can also help bring closure to cases that have gone cold. In 2006, after almost 30 years of dead ends, investigators in Virginia used carefully preserved blood taken from a 1977 crime scene in order to identify and arrest a suspect in the killing of Henry William Long.

Questions surrounding the social, ethical, and legal issues of using genetic technologies in crime investigation persist. In a few cases, geographic and ethnic genetic testing have been applied to criminal investigations to help narrow the suspect search field. Critics fear that the information gathered and stored in this type of testing could be used for research on topics such as the genetic correlates of ethnicity or criminal behavior, fueling flawed science and dangerous prejudices. These issues will influence future applications and use of this technology.

Original Program Description, 1998

We've heard a lot about DNA forensics in the news — the process of testing DNA, finding DNA matches, and creating DNA profiles of individuals makes for great headlines. But what exactly is DNA forensics, and how does it work? Is it trustworthy as evidence in court, or as proof of paternity? Can it accurately identify the deceased?

Study of our genetic identity has produced one of the most thorny ethical issues facing researchers today. Privacy and security concerns surrounding the retention of DNA samples spark heated debate. Detractors view the practice as a violation of civil rights, while proponents claim that the value of collecting genetic material far outweighs its risks, offering the potential to find lost family members and even identify "switched" babies.

Some advocates think that everyone should be genetically fingerprinted. This program looks at the laboratory techniques used to conduct DNA tests. You'll visit genetic testing labs — including the commercial facility that handled the evidence for the O. J. Simpson trial — to examine research methods up-close. You'll learn exactly how testing is performed and what the results mean. You'll also find out how forensic DNA evidence goes beyond crime-solving: into the world of missing persons, in countries where war and repression have meant the "disappearance" of millions of people. DNA technology is now being used to try to determine what happened to them.

The show also touches on ethical issues surrounding the creation of DNA databanks with the potential to retain information about each and every one of us. For example, the U.S. military and prison system already collect genetic samples from members of the armed forces and from convicts. These samples are kept "on file" in databanks for future reference. The DNA those samples contain hold far more personal information than any mug shot or inky fingerprint. Are such databanks ethical? If collection starts with the military and prisons, will it next go to schools, workplaces, or your doctor's office? Who will protect our privacy against misuse of this information?

In the end, it's up to you to examine the evidence. Is genetic testing reliable enough to permit DNA collection for government, military, or law enforcement databanks? Will someone, someday, be tracing your genetic fingerprint?