So, continuing off the last post about fingerprinting and the types and how those are collected, there is also the process of analyzing them and part of that is the people who do it.
These people are called fingerprint examiners or analyzers. They are usually trained and certified to be able to examine the fingerprints. Fingerprint examiners look at the fingerprint with a type of microscope called a loupe and they use a tool called a ridge counter to “count the fraction ridges” (“A Simplified Guide”). These examiners ultimately decide if a print is useful enough to be compared (using a computer system) to other known prints to see if the owner of the print can be found.
The image below is of a fingerprint examiner using a loupe to analyze prints.
Fingerprint examiners use what is known as the ACE-V method to examine a fingerprint. This stands for analysis, comparisons, evaluation, verification.
During the analysis portion, the print is examined to determine if it is necessary to even move on to the next stages of the ACE-V method. The quality may not be sufficient or there may not be enough of the print to be useful for a comparison. If the print is deemed usable, the characteristics that will be used in a comparison are determined. In addition, the analysis can “uncover physical details such as recurves, deltas, creases and scars that help indicate where to begin the comparison” (“A Simplified Guide”).
In the comparison part, a fingerprint examiner will look at the “known and suspect prints side-by-side.” The examiner looks at the tiniest details of the prints and the locations of those details to decide if they are a match. The next step is evaluation, where the examiner will make the call on “if the prints are from the same source” or different sources, or the examiner will decide that the results are inconclusive (“A Simplified Guide”).
The last step, verification, is when another examiner goes through the process described above with the same print to “either support or refute the conclusions” of the first analysis.
Because of the uniqueness of fingerprints, they can be used as a form of identification. No two people have the same fingerprint, as demonstrated by the FBI’s Integrated Automatic Fingerprint Identification System (IAFIS), which contains over 72 million fingerprints from various sources. Just about every time something is touched, a fingerprint is left behind, along with the identity of the owner of that print.
Source (for this post and the previous one): “A Simplified Guide To Fingerprint Analysis.”Forensic Science Simplified. 2012. Web. 4 December 2015.