With the popularity of crime and court television shows such as Law and Order and CSI, people in Pennsylvania and across the country have gained an inside look into the criminal investigation and prosecution process. Obviously, many of these television shows leave a lot to be desired in terms of realism, but one thing that is generally portrayed accurately is the law enforcement reliance on DNA evidence to apprehend and prosecute suspected offenders.

However, many do not realize that the genetic testing technology is still a relatively new phenomenon. DNA was first used as evidence in sex crimes cases in the late 1980s, but the United States' Combined DNA Index System, or CODIS, was not fully operational until 1998. Therefore, there is a long history of cases that were tried and offenders that were convicted based solely on evidence such as witness statements and victim identification.

Advocates say that these less than scientific methods of identifying a suspected offender have led to hundreds of wrongful convictions for sexual offenses and various other crimes. According to the Innocence Project, a New York-based offender advocacy group, advances in genetic DNA testing have led to the exonerations of over 260 people who served prison sentences for crimes they did not commit.

The Innocence Project says that an incorrect victim identification contributed to the conviction in over 75 percent of the exoneration cases. This result was not unexpected: the tearful in-court identification of an attacker by his victim is powerful evidence, especially when the case is being decided by a sympathetic jury. But however well-intentioned a victim may be, it can be easy to get the identification wrong. Police can unknowingly and unintentionally sway a victim during an identification, and with that strong evidence, an innocent offender may not have a chance.

Hopefully, offenders will continue to be exonerated by their DNA. However, there is no court remedy that can make up for the years many innocent defendants spend in jail for crimes they did not commit.

Source: Washington Post, "In DNA reprieves, guilt from another source", Maria Glod, 22 March 2011