Not only can DNA be used to convict criminals, it also has successfully been used to exonerate individuals, some of whom were wrongly imprisoned for more than two decades. Often, the person who's 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.

With the advent of criminal evidence through DNA, exonerations of wrongly convicted prisoners became quite common.

How Can DNA Exonerate Prisoners?

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. Moreover, if it turns out that the DNA matches a profile in a database such as CODIS, the real criminal can be located and tried. The organization claims there has been a total of 364 DNA exonerations since 1992 (as of January 2019).

DNA Evidence And The Death Penalty Debate

Opponents of capital punishment have pushed for DNA testing to be used more regularly, and even many 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 always accompanies the use of capital punishment is that the wrong person could be executed for a crime.

One case highlighting this concern involved a man who was executed in Virginia in 1992. It 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 responded to this case by arguing that claims of the death penalty's fallibility were unfounded, opponents noted that the danger of a wrongful execution still existed, and continued their call for the increased use of DNA as an identification tool.

Have Questions About DNA as an Exoneration Tool? Talk to an Attorney

When you're facing criminal charges, the outcome of your case is going to depend on the evidence presented at trial, especially if it involves DNA evidence. Sometimes this evidence can be in your favor and lead to your exoneration, if it's used and presented in the right way to the jury. This will depend on the expertise of your criminal defense attorney, some of whom specialize in DNA evidence cases. Reach out to a criminal defense attorney to discuss your case and find out how they can help.