Every fingerprint expert has his own way and style of comparison of two different sets of fingerprints impressions. One set of fingerprints belongs to a known person and have been provided to expert for comparison as a specimen set. The other fingerprint impression may be a chance print, developed and lifted from scene of crime, or it may be a disputed finger print impression on some questioned document(s) or it may be from the AFIS/AFIS i.e. available in our records.
However, consciously or unconsciously, an Expert usually conducts the following four steps, the acronym as “ACE – V” for documentation, comparison and forming a final opinion. They are :-
1. ANALYSIS – The fingerprint is examined, pattern type, available portion of finger/palm, whether requisite number of ridge characteristics available with clarity and interlinked interse.
2. COMPARISON – The search print is compared with the sample or the specimen print.
3. EVALUATION – After comparison of both sets of prints, the similar ridge characteristics, their nature and their position in regard to another neighbouring ridge characteristic, whether any dissimilarity present, are evaluated and an opinion formed.
4. VERIFICATION – Before submitting the finalized opinion to the Investigation Officer ir to the court, most of the experts get their opinion verified from their peer expert or some senior expert as a cross check so that incomplete or wrong opinion is not being forwarded to Investigating Officer and/or to court.
While examining the chance prints (scene of crime prints), sometimes they are partial, smudged or very faint and requisite number of ridge characteristics may be lacking to form an opinion thereon. Depending upon the expertise of the expert and the gravity of the concerned case, the chance prints also go through three levels of examination.
These were basically discussed in my earlier blog “FINGERPRINT IDENTIFICATION” and is being reproduced here to refresh.
FIRST LEVEL OF DETAILS:- Ridge flow, patter type, ridge count, focal points(core or delta) and orientation.
SECOND LEVEL OF DETAILS:- Ridge details( also known as Galton details ir Ridge characteristics or Minutiae). The nature of the ridge details and their relative position are the base for fixing identity or otherwise.
THIRD LEVEL OF DETAILS:- Poroscopy and Edgeoscopy.
The individualization is not possible purely on the basis of first level of details. After second and third level of details, individualization can be established without any doubts.