Not only can DNA be used to convict criminals, it has successfully been used to exonerate individuals, some of whom were wrongly imprisoned for more than two decades.
Often, the person who is wrongly convicted of a serious crime such as murder or rape has a criminal record for petty crimes, which means a record already exists. These individuals are frequently convicted on eyewitness testimony, but without any physical evidence tying them to the crime.
The Innocence Project, created in 1992 by Peter Neufeld and Barry Scheck at the Benjamin Cardozo School of Law in New York, works to exonerate people by use of postconviction DNA, in which DNA from the crime scene is tested against the accused’s DNA. Often, physical evidence from a crime is kept for many years. If the evidence includes samples of blood, hair, skin, or other evidence that can include DNA, it can often be used to prove that the person accused could not have committed the crime. Morover, if it turns out that the DNA matches a profile in a database such as CODIS, the real criminal can be located and tried. From 1992 to the beginning of 2006, the Innocence Project helped exonerate 173 prisoners.
Opponents of capital punishment have pushed for DNA testing to be used more regularly, and many of those who favor capital punishment agree that those convicted for a capital offense should be allowed to make use of all evidence. One of the fears that come with capital punishment is that the wrong person could be executed for a crime. A case involving a many who was executed in 1992 gained national attention in 2005 when Governor Mark Warner of Virginia ordered DNA testing on a 24-year-old DNA sample to determine whether Roger Keith Coleman had murdered his sister-in-law in 1981. Coleman had proclaimed his innocence, and although his DNA had been tested before his execution, lawyers said the examiner might have misinterpreted the results. Using more advanced technology, Coleman’s DNA was tested in January 2006, and the results confirmed that he was in fact the killer. Although supporters of capital punishment said that claims of the death penalty’s fallibility were unfounded, but opponents noted that the danger of a wrongful execution still existed, and called for increased use of DNA as an identification tool.