Bitemark Case Study 1

History: A young child was the victim of repeated physical abuse as documented by Child Protective Services. When the child was taken to the hospital after a recent abusive episode, photographic images of the sustained injuries documented several bitemarks, two of which were located on the arm. The time and location of the abusive episode was known and occurred in the child’s home. The child’s mother and mother’s boyfriend were the only people home at the time of the attack. Both the child's mother and her boyfriend gave law enforcement sworn statements that they were in fact present when the abusive episode occurred. In their statements, both said the other was responsible for the attack.

Additional evidence collected included DNA swabs from the bites, dental impressions of both adults’ teeth, from which dental stone models were created, and sample bites from both adults’ suspect dentitions in Aluwax® to record the arch shape and tooth positions.

The bitemarks were analyzed and then compared to the suspect dentitions. The results of the comparison showed that one of the dentitions could be excluded as the arrangement of the teeth could not have created the bitemark. The other biter could not be excluded as having done the biting. Additionally, the DNA test came back matching the DNA of this same the unexcluded biter (Figure 2).

Figure 2.
Suspect A (left) could not be excluded. Suspect B2 (right) was excluded. DNA testing came back as a match for suspect A.