Validity of Bite Mark Evidence Challenged
In 1987, Steven Chaney was convicted of murder in Dallas, Texas. The evidence that sealed his fate was bite mark testimony offered by two forensic odontologists (bite mark experts). According to the testimony, the murder victim had a bite mark on his arm that could only have come from Chaney. Texas Monthly magazine reports that this evidence convinced the jury of Chaney’s guilt, despite the fact that he had nine alibi witnesses on his side. Twenty-eight years later, in October 2015, Chaney was released from prison a free man after the forensic testimony that sent him to jail was discredited. Now, the Texas Forensic Science Commission has recommended that prosecutors stop using bite mark evidence until its scientific validity can be established.
As Texas Monthly describes, bite mark testimony has been used to support criminal convictions for decades, despite the fact that no conclusive research or studies supported it. Chaney is the 26th person to have been indicted or convicted based on bite mark testimony. Texas Monthly tells of one individual who was executed following his 1985 murder conviction, even though the only physical evidence that tied him to the crime were bite marks on the two victims’ bodies. Experts, including the National Academy of Sciences, now say there is no sufficient scientific basis to believe that a conclusive match can be determined from bite mark comparisons. Indeed, sometimes forensic odontologists cannot even agree on whether marks on skin are human bite marks or something else.
The Texas Tribune reports that the Innocence Project, a nonprofit national organization dedicated to exonerating wrongfully-convicted individuals through DNA evidence, asked the Texas Forensic Science Commission to investigate the reliability of bite mark evidence after Chaney was cleared. After its investigation, the Commission recommended a moratorium on further use of bite mark evidence in criminal prosecutions while more research is done. The Commission’s general counsel reported that one of the primary concerns is whether skin can record bite marks with sufficient fidelity that a comparison can be made.
The Commission, well-respected and influential throughout the country, is the first organization of its kind to make such a recommendation, and experts expect other jurisdictions to sit up and take notice. Note, however, that the Commission has no authority to compel prosecutors to stop offering bite mark evidence, nor can it keep courts from accepting it.
Consult a Miami criminal defense attorney
If you have been charged with a crime, you need a top-notch defense lawyer to protect your rights. The Miami and Orlando criminal defense attorneys of The Baez Law Firm have a thorough understanding of forensics and the ability to do our own analysis of the forensic evidence in your case. We do not accept what anyone has to say about the evidence until we have run the tests ourselves. For a free consultation on your case, contact The Baez Law Firm today.