8127/frame/fm

 
3.
Inferential Reasoning in Forensic Science
Based on our discussion so far, we propose the following as a basic tenet of
forensic science:
We have already encountered one process used by the forensic scientist that
ends in an inference, that of source determination. We have also established
that the law requires another inference to make this source determination
relevant evidence. We now explore further the misunderstandings and
debates about this latter process of associating two or more objects through
an inference of contact.
 
a.
Association and Interpretation — A Divergence 
of Understanding
It is noteworthy that so little has been written using the term 
 
association
in
the forensic science literature. The few references that one can find among
textbooks consist of short fragments that are incomplete and rarely help to
uncover what is meant by the term.
Osterburg (1968) asserts that associative evidence is “linking a person to
a crime scene.” Stoney (1984) describes it as “linking a suspect with an
offense” (not exactly the same meaning as Osterburg’s). DeForest et al. (1983)
talk about the “association between people and the physical evidence.” With-
out using the word association, Kirk (1953; 1974) offers that the “identifica-
tion of a murder weapon may lead to its possessor at the time of the crime,”
a clear attempt at connecting an item of physical evidence with a perpetrator.
Absent from any of these meager attempts to define association is a
discussion of how one proceeds from linking evidence and reference to a
connection between people, places, and things. The implication is that once
the source of the evidence has been determined, the association follows
without question. No mention is made of the assumptions that must under-
gird the inferences of various associations, or of alternative possibilities that
might also explain the recovered evidence.