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180 AUTOMATED FINGERPRINT IDENTIFICATION SYSTEMS

responsibility is to work on AFIS systems might, for example, have some idea
of how the AFIS system performs its search or matching function and thus can
exploit the features of the system to find as many minutiae as possible. Such
features could include use of light filters, use of offset lighting, searching only
a portion of the database, or some other technique that could improve the like-
lihood of a match.
If the crime scene examiner is also the latent print examiner, the amount of
time spent on each function is limited by the amount of time spent on the other
function. Spending time at a crime scene results in fewer hours for searching
the AFIS system for a match.

8.5.2 THE SEARCH DATABASE
Once the latent print is collected and digitized by the latent print examiner, it
is searched against the AFIS database. The database may be as small as a few
thousand records or as large as several million. It may be specific to some
common characteristic, e.g., a search of all tenprint and criminal records on
file, or it may be a subset of a larger database, such as only those tenprint
records with an arrest. Questions that might be asked about the characteristics
of the AFIS database include the following:

1. What are the criteria for inclusion in the search database?
2. Was the best card selected for conversion?
3. How many records are stored on the latent cognizant database?
4. How many records are added, deleted, or updated annually?

Each of these questions is discussed in the sections below.

8.5.2.1 What Are the Criteria for Inclusion in the Search Database?
If the database is a criminal or forensic database, it holds the records of all
persons fingerprinted for a criminal offense and certain other categories. In
general, the database for searching latent prints includes the images of indi-
viduals whose finger images are likely to appear at a crime scene. In addition
to those previously arrested and fingerprinted, the prints of law enforcement
personnel and other public officers may be included in the database.
The reason for including criminal offenders in the database is apparent, but
what is the reason for including law enforcement and other personnel? Latent
fingerprints found at the crime scene may include those of law enforcement
personnel who were not strictly adhering to preserving the scene. In the after-
math of September 11, many agencies are including the finger images of all
personnel whose latent prints might appear at a crime scene, including
firefighters.