When Is a Criminal Defendant Allowed to Seek Post-Conviction DNA Testing of Evidence?

August 1st, 2019 by Tad Nelson in Criminal Defense

You have probably heard about cases where a criminal defendant was exonerated because of DNA evidence. In some cases, this evidence is not discovered (or properly tested) until after the defendant’s original trial. It is therefore possible to file a post-conviction motion to obtain DNA testing in certain circumstances.

Houston Court Rules Robbery Defendant May Not Seek DNA Sample from Accusing Witness

But there are limits to a defendant’s rights in this area. A recent decision from the Texas First District Court of Appeals here in Houston highlights one such limit–namely, that a defendant does not have the right to ask for additional DNA samples that were not previously entered into evidence.

In this case, Castro v. State, prosecutors charged the defendant with aggravated robbery with a weapon. At trial, a witness testified the defendant put a handgun to her stomach and proceeded to take her wallet. The witness said she got away, and the defendant left the scene with another man. Police later arrested the defendant at a nearby store and recovered the wallet and a handgun from his vehicle.

The jury found the defendant guilty. Afterwards, the court agreed to the defendant’s request for post-conviction DNA testing of the wallet, the handgun, and a hat the defendant allegedly wore during the robbery. The testing found there was no DNA sample from the defendant on the wallet, the handgun “had no discernible DNA on it,” and the hat had DNA samples from two people, one of whom might have been the defendant.

Based on these results, the defendant asked for additional DNA testing. Specifically, he wanted the court to order the witness to submit a DNA sample so that it could be compared to the samples previously taken from the wallet. The judge denied this motion, prompting the defendant’s appeal to the First District.

But as the appeals court explained, the defendant was not entitled “to post-conviction testing to ascertain the presence of another person’s DNA.” Post-conviction testing is not a constitutional right. Rather, it is a function of state law, which only provides for such testing of an item “that is in the possession of the state during the trial of the offense” alleged. Since the prosecution never had the witness’ DNA available at trial, the defense was not entitled to it now.

Furthermore, such testing would not exonerate the defendant. The prior testing already established his DNA was not present on the wallet. Whether or not the victim’s DNA was on the wallet was essentially irrelevant, the Court said.

Speak with a Galveston or League City Criminal Defense Lawyer Today

Despite the ruling in this case, post-conviction DNA testing can often prove the difference between a wrongful conviction and an exoneration. If you have additional questions or concerns about how DNA testing is used by the state, our experienced Houston criminal defense attorneys can help. Contact the Law Offices of Tad Nelson & Associates today if you have been charged with a criminal offense and require immediate assistance. Call (281) 280-0100 .


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