Page 194 - Automated Fingerprint Identification Systems (AFIS)

STANDARDS AND INTEROPERABILITY 179

Figure 8.4
Searched
on Latent Prints Searched on
AFIS the AFIS System
Agency A Agency B

50 prints from 5 70 prints from 7
cases cases

50 prints from 5 cases searched on AFIS 70 prints from 7 cases searched on AFIS
AFIS produces 25 Idents AFIS produces 25 Idents

• 50% of AFIS searches
• 25% of cases are cleared by elimination prints

The hit rate for Agency B may be

• 35% of latents (25 AFIS idents of 70 latents searched on the AFIS system)
• 57% of cases (25 idents in three of the seven cases)
• 35% of AFIS searches
• 0% cleared by elimination prints

This example demonstrates the possible differences in statistical reports
depending on the way in which the latent images taken from the crime scene
were processed. The variation does not speak to the dedication and resolve of
the evidence technicians and crime scene specialists who work on the identifi-
cation process. If the purpose of this statistical information is to provide a clear
picture of current operations and provide opportunities for improvement, then
some of the differences between the two agencies are relatively minor. What
does become apparent is the effect of elimination prints in improving the iden-
tification rate.

8.5.1.5 Who Searches the Latent Prints on the System?
For clarity, in the example above, it was assumed that the AFIS operators were
equally proficient in using the AFIS system. However, this is not always the case.
If an agency has latent print examiners whose responsibilities are limited
to latent print searching, not latent print collection, they can specialize in the
technical skills useful for identifying the greatest number of minutiae in the
latent print. That is, by concentrating on using the AFIS system as a search
tool and knowing the unique features of the AFIS system, the latent print
examiner would be able to make more identifications than an examiner who
uses the AFIS system only occasionally. Latent print examiners whose primary