Examination of Firearms Review: 2007 to 2010 - Interpol

Furthermore, the authors propose to consider the premises of fingerprint
individualisation (persistence, unicity and classifiability) as a theory, hypotheses that
have not been falsified through testing to date and therefore, being supported by
evidence, have gained the status of theory (184). ACE-V, as applied by fingerprint
examiners in a laboratory, has been tested in order to assess the accuracy,
precision, reproducibility, repeatability and biasability of conclusions. Overall, three
erroneous identifications (out of 720 comparisons) were observed but were attributed
to transcription errors. Two of these were submitted in the course of the study to
verification and were not verified, while the third erroneous identification was resubmitted
to the same analyst, who did not repeat the error. Erroneous exclusions
were more prevalent and less likely to be caught in verification. Also, divergences
appeared between definitive exclusions (identification/exclusion) and inconclusive /
no value conclusions. In particular, some comparisons resulted in ‘identification’
decisions from some examiners, and in ‘inconclusive’ decisions from others (185).
Accuracy in fingerprint comparison has been tested using laypeople (186) ; it is
shown that some fingers are more easily discriminated than others.
Whether written training programs exist, whether they adhere to SWGFAST
guidelines, whether the interpretation of these guidelines is consistent, and whether a
difference exists between ASCLD/LAB accredited agencies and non-accredited
agencies concerning the training standards has been investigated by the means of a
survey (187). Out of 168 surveys sent out to members selected from the 2007
International Association for Identification directory, 75 were returned. 75% of the
respondents claimed having a written training program, and 72% claimed adhering to
SWGFAST guidelines. Five follow-up questions were used to determine whether
these agencies actually did follow the guidelines, and, based on these follow-up
questions, only 25% do. As to the consensus in the interpretation of the guidelines, it
exists in 7 out of 11 categories tested; the four categories where no consensus was
apparent are degree requirements, the duration of the training program and of
supervised case review, and the existence of a written pass or fail policy. There was
a significant difference between accredited and non-accredited laboratories on a
majority of the points examined, and the hypothesis that there is no difference
between these two types of laboratories was therefore rejected.
The shortcomings of current proficiency tests for estimating error rates and a way to
obtain error rates for fingerprints through proficiency tests is discussed in (188).
An argument for several verifications, including an economic perspective has also
been presented (189).
2.2 Fingermark composition, detection and visualization
This chapter is structured as follows: the first section is dedicated to the composition
and evolution of the fingermark residue under various environmental conditions. It is
followed by the presentation of the recent developments in fingermark detection, the
scientific contributions being classified according to the technique, the context, or the
substrates.
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