As of today, bite mark evidence has led to more than two dozen wrongful arrests or convictions. Two men sentenced to death on bite mark evidence were later exonerated by DNA testing. Multiple proficiency tests have shown that bite mark analysts can’t even agree on whether marks on human skin were made by human teeth or teeth at all, much less agreement on which set of teeth made them. There are two underlying assumptions that need to be true in order for bite mark evidence to be valid — that the marks we make when we bite are unique to us and that human skin is capable of recording those marks in a way that allows analysts to distinguish them. So far, there is no scientific research to support either assumption, and the research that has been done suggests both claims are false. Bite mark evidence has been strongly criticized by several scientific bodies, including the National Academy of Sciences (NAS) and, most recently, by the President’s Council of Advisors on Science and Technology (PCAST). The Texas Forensic Science Commission, a body convened specifically to review the validity of questionable fields of forensics, recommended a moratorium on the use of bite mark analysis in court. Read more >>