Bite mark analysis has zero scientific validity, yet at least 36 people served decades in prison because forensic dentists claimed they could match teeth to skin wounds

Forensic odontologists have testified in criminal trials for decades that they can match a bite mark on a victim's skin to a specific suspect's dental pattern 'to a reasonable degree of scientific certainty.' This claim has no scientific foundation. The 2016 PCAST report to the President found that bite mark analysis lacks foundational validity, meaning no properly designed study has ever demonstrated that forensic dentists can reliably match bite marks to specific individuals. The error rate is unknown because the method has never been rigorously tested. Despite this, bite mark testimony has been admitted in courts across the country and has contributed to at least 36 wrongful convictions, according to the Innocence Project. Keith Harward served 33 years in prison because two forensic dentists told juries his teeth matched 'to a scientific certainty.' Steven Mark Chaney was convicted of murder in 1987 despite having nine alibi witnesses, because a bite mark analyst said his teeth matched. Chaney was declared 'actually innocent' in 2019 after the forensic dentists recanted. The real cost is measured in human lives destroyed. Ray Krone was sentenced to death, reconvicted and sentenced to life, and spent over a decade in prison before DNA evidence identified the real killer. Levon Brooks, Kennedy Brewer, and Keith Harward collectively spent over 65 years in prison for crimes they did not commit, convicted largely on bite mark testimony. Eddie Lee Howard sat on death row in Mississippi until 2021, when crime scene DNA was matched to someone else. In each case, the actual perpetrator remained free while an innocent person served time. The victims' families were denied real justice because the wrong person was convicted. The forensic dentists who provided the testimony faced no professional consequences. Bite mark analysis persists because it exists in a regulatory vacuum. There is no licensing requirement for forensic odontologists, no mandatory proficiency testing, no standardized methodology, and no external validation body. The American Board of Forensic Odontology sets its own standards and investigates its own members. Courts continue to admit bite mark testimony because of legal precedent: once a type of evidence has been admitted by one court, other courts follow suit under the doctrine of stare decisis, regardless of whether the underlying science has been debunked. Overturning a conviction that relied on bite mark evidence requires individual post-conviction litigation, which is expensive, slow, and depends on the availability of alternative evidence like DNA. Many defendants convicted on bite mark testimony have no remaining biological evidence to test.