8127/frame/fm

Subjective.
This implies a criteria that is personal and, as such, may be
different for each individual. It is important to understand that any endeavor
in which humans participate involves a subjective component; it is the nature
of human existence that we each operate from a slightly different perspective,
and all of our decisions are shaped by our cumulative experiences. Science
is no different and the subjective element makes our conclusions no less valid.
According to Popper, “We must distinguish between truth, which is objective
and absolute, and certainty, which is subjective.”* (Horgan, 1996).
One fingerprint expert may be “certain” when she can find 9 points of
comparison between two prints; another expert may require 10 points of
comparison to be “certain.” Even if the two experts agree that 9 points of
comparison exist, they may come to different conclusions based on their
subjective uncertainty. The chromatogram of a suspected ignitable liquid is
an objective piece of data. Everyone can agree on the number of peaks and
their size. Two qualified analysts might disagree about whether they are
comfortable concluding that the chromatogram represents a highly evapo-
rated sample of gasoline.
Most.
Not all qualified observers might agree with the assessment. This
derives in part from the subjective nature of the evaluation, and in part from
the nature of our culture, which seems to require disagreement to instigate
progress.** However, if you are hanging in the wind all by yourself with a
conclusion of singular common source, and none of your lab-mates is willing
to brave the storm with you, you might wish to reconsider your conclusion.
* Popper believed that a theory 
could
be absolutely true, but rejected the belief that we
could ever 
know
that a theory is true (Horgan, 1996).
** “The reasonable man adapts himself to the world. The unreasonable man persists in
trying to adapt the world to himself. Therefore all progress depends upon the unreasonable
man” — George Bernard Shaw.
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Principles and Practice of Criminalistics