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Inductive inference is a primary tool for evaluating 
physical evidence gathered from a criminal event.
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Principles and Practice of Criminalistics
Another body of forensic literature emphasizes understanding the nature
of the factors leading to deposition of the evidence, and how, after analysis,
evidence should be interpreted in the context of the case. In these writings,
the word 
 
interpretation
appears frequently. For example, Cook et al. (1998a)
contend that the process of interpretation is “drawing rational and balanced
inferences from observations, test results, and measurements.” Taroni (1998)
asserts that “appropriate interpretive procedures … need to be applied … to
aid in the correct interpretation of scientific evidence.”
The difference between association as an adjunct to individualization
and interpretation as a separate process amounts to more than a mere con-
trast in emphasis; it is a divergence in understanding the fundamental role
of science in legal matters. This leads to confusion among practitioners of
forensic science and between the service provider and the client; it raises the
decibel levels during debates and hearings, and hinders progress in the incor-
poration of science into law.
Two well-known figures serve to draw a sharp contrast between the two
schools of thought:
Paul Kirk — “The criminalist does not attempt identification except as a
prelude to his real function — 
 
that of individualization
”
 
 [
emphasis added]
(1953; 1975).
Henri Poincaré — “An effect may be the product of either cause A or cause
B. The effect has already been observed; one wants to know the probability
that 
 
it is the result of cause A
” [emphasis added] (Taroni, 1998).
These two quotes reveal a clear difference in the perceived role of the scientist
in legal matters. Kirk believes that the scientist is to determine the 
 
source
of
the evidence; Poincaré believes that the scientist is to assist the fact finder in
establishing the 
 
cause
of the evidence.* This divergence forms the central
theme of a continuing debate between jurists and scientists over the function
of science in the legal arena.