Advances in Fingerprint Technology.pdf

correspondence in friction ridge detail that is necessary for a conclusion of
identity has not been established. There is an even more basic deficiency,
however. There is no methodology in place that is capable of measuring the
amount of correspondence in a fingerprint comparison. And there is a third,
corollary deficiency: there is no methodology in place that is capable of
measuring the amount of detail that is available in a fingerprint for comparison
to another. In summary, one cannot:
1. Measure the amount of detail in a (single) fingerprint that is available
to compare
2. Measure the amount of detail in correspondence between two fingerprints
3. Objectively interpret the meaning of a given correspondence between
two fingerprints
AFIS technology, while holding promise in these areas, has been and
remains restricted to the task of screening millions of prints and efficiently
selecting candidates for fingerprint comparison. Although this is an important,
effective and, indeed, revolutionary task, the comparison itself is
reserved for the individual fingerprint examiner. The examiner applies personal,
subjective criteria that, despite all its historical precedent, legal acceptance,
and public confidence, are both vague and flexible.
Although not directly the subject of this chapter, the above deficiencies
are compounded by the fact that neither the education of fingerprint examiners,
nor the process of fingerprint comparison is standardized. Furthermore,
there have been no objective studies providing validation of the
subjective processes that are in place.
Recognition of the above deficiencies does not mean that the fingerprint
practices are discredited, that they have no foundational basis, or that the process
is necessarily unreliable. Given the Daubert criteria, 2 however, the question of
reliability is a reasonable one to ask. Legal scrutiny of fingerprints is, after more
than 80 years of uncritical public and judicial acceptance, entirely appropriate.
Without objective standards, however, what foundational aspects for
fingerprint identification do we have?
The Laws or Premises Underlying Fingerprint Identifications
For many years, two “laws of fingerprints” have been asserted as the foundation
for fingerprint identifications: 3
1. Fingerprints never change (apart from temporary abrasion and permanent
scarring).
2. No two fingerprints (made from different fingers) are alike.