Boston P.D . two (2) fingerprint lab examiners testified that a fingerprint from a drinking glass used by the assailant matched Cowans’. He was sentenced to 35 to 50 years in prison.
DNA testing revealed the error. An investigation of the misidentification concluded that poor training of the department’s fingerprint analysts was to blame for the blunder. Finding that the examining officers were not prepared to do complex fingerprint analysis, the report said the unit did not train its officers to keep up with standard practices in fingerprint analysis and had low performance standards. The unit had little or no protocol or standardization of procedures. This resulted in the closing of the Lab. and training all new civilian examiners. The error would not have been found and corrected if not for the Innocence Project .
L.A P.D. is in a similar situation, discovery of two (2) bad identifications has led to the review of close to 1,000 latent cases. Again a situation where policy/procedure and training will be a contributing factor in the errors.
What happens when a latent image is only searched once in the Automated Fingerprint Identification System, is it truly a non-ident ? The answer is positively, Maybe
Latent and tenprint image clarity as well as the size of the database play a big roll in whether a latent image is identified on its initial search in
the Automated fingerprint database. I can tell you from experience, there are a significant numbers of tenprint arrest cards in most search
databases with poor clarity that negatively impact a latent search. Many agencies, because of workload or lack of understanding of the system,
do not normally search a latent in the automated system more than once. National Institute of Standards and Technology (NIST) a few years
back tested the search accuracy of the major AFIS vendors and discovered an accuracy rate of between 54% and 85%. To get the 85%
accuracy requires the vendor test on a small database with a minimum of 15 minutiae on the latent and the corresponding minutiae are on the
target image in the search database. I don’t mean to fault the search systems which are producing good suspects resulting in fingerprint
Identifications, but agency procedures need to compensate for system limitations.
There is also another scenario where on the initial search the examiner missed an identification. In the 2 nd . Search hopefully the target is not
missed for a 2 nd . time. If a print that could be identified is not how does it impact your case ?
Whether a prosecutor or defense attorney, a missed identification on an unidentified latent can have a major impact on your case or client. It
could produce the individual that was responsible for a criminal act or a witness that may be able to add more detail to a case. If not identified
the missed identification could lead to additional criminal acts by the individual or a wrongful conviction in the current case.
Most systems being purchased today have a palm search capability. A great benefit to image identification there will be significantly more Latent image individualizations. We can also expect an increase in errors with the same issue’s now encountered in fingerprint identification. While we increase the number of minutiae available the individualization is done exactly the same as a fingerprint individualization.