What is Bite Mark Evidence?
If a victim of a crime is bitten, the impressions of a suspect’s teeth can be taken and compared to the injuries sustained by the victim. Forensic dentists examine the victim’s bite mark for characteristics and arrangement of the teeth.
Criticisms of Bite Mark Evidence
Forensic dentistry has been heavily criticized for having some of the highest error rates amongst the forensic identification specialties. Upon review from the committee from the National Academy of Sciences, experts concluded that bite mark similarities are insufficient evidence to incriminate an individual to the exclusion of other suspects.
The suspicion over the accuracy of this evidence comes from the nature of our skin. The skin changes over time: it is elastic, responds to injury with swelling as it repairs, changes as it is moved, and is uneven. Additionally, there is no consensus that teeth are individual to a person. Furthermore, there is a limited sample size when forensic scientists make models of the teeth. All 32 teeth are not likely to leave a clear impression on a victim’s skin; it may be 4-8 biting teeth that leave an impression. From that limited sample size, 2 people are increasingly likely to have similar biting teeth. A bite mark made by one person, therefore, may be matched to another innocent individual due to the nature of skin and the similarities between individuals’ teeth.