Overview Fingerprint conclusions are expert judgments. These specific types of judgments may be more appropriately termed as inferences, or subjective probabilities, where frequency rates have not been able to be calculated. For over a hundred years researchers have attempted to…
Category: Impression & Pattern (page 5)
The Emperor’s New Clothes: A Guide to Latent Print Testimony
Overview In the tale of the Emperor’s New Clothes, a vain emperor commissions a new set of robes that he is told will be invisible to anyone who does not deserve his position, or is extraordinarily stupid or foolish. Of…
The Basics of Error Rates in Pattern Evidence
Overview Originally presented at the 2015 Impression, Pattern and Trace Evidence Symposium. One of the Daubert prongs of admissibility for scientific expert testimony is the known or potential error rate of a technique. Thus, examiners are often asked about the…
Swipes, Wipes and Transfer Impressions
Overview Swipes, wipes and transfer impressions are the only bloodstain patterns not created by blood in flight (with the exception of flowing blood). The patterns adhere to Locard’s principle which states that when two objects come in contact with each…
R&D 2014 – Fundamental Forensic Science Research-Part II
Overview This archival portion of the 2014 R&D Seminar Series covers the following presentations: Quantitative Metrics of Friction Ridge Detail Derived from Information Theory by Thomas Busey Definition of the Concept of Sufficiency in Latent Print Examination by Cedric Neumann…
R&D 2014 – Fundamental Forensic Science Research – Part I
Overview This archival portion of the 2014 R&D Seminar Series covers the following presentations: Review on some Fluid Dynamics Aspects of Bloodstain Pattern Analysis – Daniel Attinger From Basic Research to Routine Use in the Courtroom: Elemental Analysis and Comparisons…
Shooting Reconstruction: 4 Elements of Trajectory
Overview A key part of any shooting incident reconstruction is the determination of a projectile’s trajectory through items at the scene. The path of a bullet hole has 4 main elements that require measurement, estimation, or other determination where possible.…
New Paradigm for Fingerprint Reporting
Overview In November 2015, the Defense Forensic Science Center (DFSC) issued an Information Paper announcing the decision to cease the use of the terms “individualization” and “identification” in latent print technical reports and expert witness testimony. This webinar provided an…
Magneto-Optical Sensor Roundtable
Overview The discovery of more effective methods to detect and restore erased markings in firearms is of great interest to firearm examiners, in particular the invention of new nondestructive methods. Magneto optical (MO) sensor technology may address this need. Earlier…
Latent Fingerprints: Reducing Erroneous Exclusions
Overview This presentation discusses reducing erroneous exclusions in latent fingerprints. The exclusion decision is a fairly recent change in latent print comparisons, and the discipline is still struggling with how to handle exclusions. Erroneous exclusions are being discovered with surprising…