DNA, or Deoxyribonucleic Acid, is a “fingerprint” found in biological tissues and fluids, such as:

  • Saliva
  • Hair
  • Semen
  • Skin
  • Blood
  • Sweat
  • Tears

Who Uses DNA Criminal Evidence?

1) Prosecutors. Over the past 20 years, prosecutors in criminal cases have been using DNA testing to prove that the suspect was at the scene of the crime. This can be powerful evidence, since DNA can give nearly exact matches with relative certainty.

2) Defense Attorneys. DNA testing can also be used by the defense to show that the suspect was not at the scene of the crime and prove the defendant’s actual innocence. However, keep in mind that just because there was no DNA was found at the crime scene it does not mean that the defendant was not there.

Additionally, during trial, defendants may argue that test results were not accurate because of the corruption of the DNA sample, or because only a few identifying segments of the DNA were obtained. Also, the very certainty of DNA testing can be disputed. The defense can argue that each segment represents a binary value, such that the odds of a match are much lower than the purported 1 in 100 billion.

3) Innocence Projects. Organizations, such as the Innocence Project, that are working to exonerate the wrongfully convicted, rely largely on DNA testing. This type of testing is crucial for their work, and they are succeeding in a number of cases they accept. DNA testing has exonerated 245 people, including 18 on death row.

Where Is DNA Testing Available?

Currently, all states allow inmates claiming innocence access to DNA testing, although many of these statutes limit how far these tests can go. If you have questions regarding DNA testing in your state, you should consult an attorney.

Seeking an Attorney’s Help

If you have criminal charges against you, or have been wrongfully convicted, you should to contact a criminal lawyer immediately to ensure your rights are protected. Hiring an accomplished criminal defense attorney may help you identify flaws in a DNA test that may discredit untrustworthy results. If you have been convicted, speaking with an attorney may help you gain access to post-conviction DNA testing.