Latent Print Evidence Evaluations

 

We have a unique combination of academic, statistical, practical and professional experience in latent print examination. Included are a PhD Dissertation, National Institute of Justice Research, leading scientific and legal publications, membership on the Scientific Working Group on Friction Ridge Analysis, Study, and Technology (SWGFAST), appointment to the Physics/Pattern Interpretation Scientific Area Committee within NIST’s Organization of Scientific Area Committees (OSAC), participation on the NIJ/NIST Expert Working Group on Human Factors in Latent Print Analysis, and extensive casework reviews / testimony.

Latent print examination standards and practices are a rapidly changing area in forensic science. As one of the most definitive methods of identification, and one of the most common types of evidence, it is essential that latent print evidence be effectively reviewed prior to its appearance in court.

Our evaluations include:

Expert re-examination of finger or palmprint comparisons, together with related documentation such as laboratory, crime scene and police reports, associated notes, expert’s credentials and laboratory procedures.
Review of crime scene technician methods, documentation, statements and conclusions regarding the search for, location and recovery of prints.
Re-examination of items or crime scene locations to verify the surface and position from which prints were recovered.
Review of decisions made regarding the usefulness of evidence prints for identification or exclusion.
Examination of unidentified prints and determination of suitability for exclusion of the defendant, or for comparison with alternative suspects or co-defendants.
Evaluation of collateral issues such as where exactly the prints were found, the corresponding position of the hand, how the item was touched, what other prints are nearby, etc.
Evaluation of very small latent print fragments for correspondence to specific individuals and, where they correspond, estimation of the weight of evidence supporting that individual as the source of the print.
Determination of whether or not there is a scientific or technical basis on which to challenge validity, admissibility, or credibility. Suggestions for possible further actions.

imageA poor quality smudge from a finger, useless for identification, that was identified through testimony of a police officer during a preliminary hearing. The error was caught by re-examination, resolved by exposure to the court and dismissal of charges.

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Illustration of a mis-identification by a certified latent print examiner. Marked enlargements of a latent fingerprint (right) as identified to an inked fingerprint (left). This mis-identification was caught before trial and brought to the attention of the prosecutor. This led to dismissal of charges in this case, review of the fingerprint examiner's work and the discovery of numerous prior cases of either mis-identification or identifications made with insufficient correspondence.


 

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A small latent print fragment (left) and a candidate source found using AFIS technology (right).