Experimental Design with Respect to PCAST Report Subsection on Bite Marks
After reading the PCAST report section on Bite Mark Analysis I understood that there were many issues with the implementation of examination. It appears that the examiners do not follow a set protocol to identify markings. Each examiner is left to their own methods to identify bite marks. The first thing I would do is construct a set of conventions for the examiners to follow. I would consult odontology experts to set these guidelines. Perhaps the high rate of error is due to practitioners using different identification techniques.
A study from 1975 indicated that correct identification was more likely to happen immediately after the bite mark was acquired. However, this factor hasn’t been further examined with newer technology. For this reason I would photograph bite marks at different time intervals to see what impact time has on the accuracy of the examiner.
The treatment in my experiment would be twenty-four individual biters. I would take dental molds of twenty of these subjects. Therefore the response of the examiner could be “match”, “no match” or “inconclusive”. The biters would each bite pig skin to simulate human flesh. Then the skin would be photographed at different time intervals of 0, 2, 10, and 24 hours. The photos would be scanned into a computer. After all the treatments were gathered then eight examiners, units, would evaluate the samples. Four examiners would be American Board of Forensic Odontology Certified Analysts. The remaining four would be practicing dentists. This measure of having examiner blocks would achieve replication. Each examiner would analyze five samples from each time period and four non-matches. The examiners would be given the information that a non-match is a possible conclusion thus providing randomness.
I would be interested to see what an experiment such as this one would show or indicate for the future of bite mark analysis. This experiment would be expensive. The payment of participants (biters and examiners) and the acquisition of materials (pig skin and technology) would no doubt be costly. According to PCAST forensic odontology is not an accurate scientific method to determine a person’s innocence or guilt and therefore shouldn’t be used. This would make funding a study such as this near impossible.