Bite mark analysis is an area of “science” that is unique to crime investigation. Forensic dentists are usually self-employed and have no oversight. There are no rules or regulations governing the industry, and no government entity has ever reviewed the validity of bite mark evidence.
From the start, bite mark analysis has been a dubious science. As the Chicago Tribune outlined, the field was born in 1970 when eight dentists sought to seek recognition from the American Academy of Forensic Sciences as a legitimate way to identify criminals, but they needed 10 members. They scoured the meeting rooms and were able to find 2 other pathologists who also happened to hold dental degrees.
The field hasn’t improved much since then. 42 years later and forensic dentists still disagree about whether or not a particular mark is even a bite. Thanks to DNA testing, we now know that innocent people have been convicted in cases where the primary evidence was bogus bite mark analysis.
A bite leaves an imperfect impression on the skin, and irregularities in bodies cause distortions. Furthermore, teeth, unlike DNA or fingerprints, are impermanent. Even a study conducted by the American Board of Forensic Odontology found a 63.5% rate of false identifications, and yet courts continue to accept bite mark analysis into evidence.