Bitemarks 355
so on, as many times as there are independent variables. The same concept is
used in DNA analysis and fingerprint analysis. In the most often cited work
on the subject of the uniqueness of teeth, the use of the product rule is essen-
tial to the conclusion.^54 As discussed earlier in the section on uniqueness,
there are divergent views on the independence of those variables (events),
that is, the positions and characteristics of the biting surfaces of the anterior
teeth. Until significant research shows that the dental features are indeed
independent, mathematical or statistical certainty cannot be assigned to
either the features of the biting surfaces of the anterior dentition or to the
marks that those teeth make in skin.
As an alternative to those mathematical or statistical methods, research
currently under way on collecting and recording data on the frequency of
dental variation features is encouraging. This same type of analysis is used in
associating persons based on mitochondrial DNA (mtDNA) and in analyzing
patterns of present, missing, unrestored, and restored teeth for dental identi-
fication74,75 (see also Chapter 7). To date there is insufficient scientifically con-
firmed information to support the association of bitemark patterns on human
skin and sets of teeth with statistical or mathematical degrees of certainty.
14.4.4 ABFO Bitemark Workshop 4
One of the most contentious issues in forensic dentistry began as a well-
intentioned educational exercise. This 1998–1999 exercise was the fourth in a
series of American Board of Forensic Odontology (ABFO)–sponsored work-
shops sta r ted in 1984 a nd intended to develop g uidelines a nd best pract ices for
the scientific analysis of bitemarks. Thirty-two ABFO diplomates participated
in the 1998–1999 workshop and examined four cases. The same seven sets of
dental models served as the potential biters in all four cases. In only one of the
cases, a bitemark in cheese, was the identity of the true biter known. The other
cases came from casework selected by the workshop leaders. In only one of
the three cases of bitemarks on skin was the true biter known. This knowledge
was based, at least in part, on the victim’s identification of the biter and the
biter’s subsequent confession.^76 Participants were asked to analyze each case
and answer questions relating to the evidence. Results were tabulated and two
nondiplomates were authorized to perform a statistical analysis of the results
and produce a paper for submission to a refereed journal. The first journal to
which the paper was submitted, the Journal of Forensic Sciences, rejected the
paper, citing the inappropriate design of the workshop for statistical analysis.
Perhaps unfortunately, considering the later misinterpretations, the article
was submitted to other journals and was ultimately published in 2001 in the
journal Forensic Science International. In the paper the authors stated that the
primary objective of the study was “to determine the accuracy of examiners in
distinguishing the correct dentition that make a bitemark,” and the secondary