Page 202 - Automated Fingerprint Identification Systems (AFIS)

STANDARDS AND INTEROPERABILITY 187

Table 8.2
Latent Print Count and Hit Rates

Number of
Records in Number Number
Lat Cog of Latent of Latents Number Ident Hit
Agency Database Cases Searched of Idents Count a Rate b Notes

Police Dept 1 183,000 ? 844 79 One All
Police Dept 2 150,000 1,100 2,830 220 # Hit Unique 550 idents over 2.5 years
Police Dept 3 15,000 — 1,218 195 # Hit All
Police Dept 4 190,500 1,600 1,600 375 One Unique
Police Dept 5 200,000 2,119 5,337 1,061 # Hit Include
Police Dept 6 700,000 4,732 12,450 1,374 Multiple Unique 656 unique Individuals
Police Dept 7 245,000 — — — One Unique
Police Dept 8 245,000 410 1,230 127 One Unique 91/127
State 1 741,000 3,700 6,200 419 # Hit Unique
State 2 220,000 2,465 4,943 357 # Hit Multiple Tracked by image, not
case
State 3 1,028,000 4,700 8,015 569 Multiple Unique 505 cases, 569 latents
State 4 684,000 1,055 1,748 271 Multiple Unique
State 5 1,089,000 7,168 21,504 781 Multiple All
State 6 1,500,000 30,000 50,000 704 Multiple Multiple
State 7 641,000 725 4,860 158 One Unique 86 cases, 158 idents
Totals 7,831,500 59,774 122,779 6,690

a
Count: One, one ident per case regardless of number of lifts hit; multiple, multiple idents per case only if more than one individual is identified
with lifts from that one case; # hit, number of latent prints hit (i.e., three lifts hit in one case from the same SID produces three latent idents).
b
Hit rate: All, all latent cases received by the site/latent unit (regardless whether searched on AFIS); unique, only unique cases searched on AFIS
regardless of number of times searched on AFIS (one case received, entered on AFIS regardless of the number of searches performed = one case);
multiple, includes multiple searches of the same case (one case received, entered on AFIS, searched five times = five cases).

The local department is referred to as Agency 1 and the state department as
State 1.
What are some of the differences between these two agencies?

• The local agency collects its own latent prints, assuring a more direct level of
continuity and this is usually lifted by an evidence technician.
• Agency 1 uses the lifts, State 1 has photos, one step removed from the
evidence.
• Agency 1 always has the person who lifts the prints at the crime scene follow
the case through AFIS; State 1 does not.
• The two agencies use different techniques that employ system search
parameters.