A green fingerprint icon on a light gray background.

Journal: Daedalus

Published: 2018

Primary Author: Joseph Kadane

Secondary Authors: Jonathan J. Koehler

Research Area: Latent Print

Everyone knows that fingerprint evidence can be extremely incriminating. What is less clear is whether the way that a fingerprint examiner describes that evidence influences the weight lay jurors assign to it. This essay describes an experiment testing how lay people respond to different presentations of fingerprint evidence in a hypothetical criminal case. We find that people attach more weight to the evidence when the fingerprint examiner indicates that he believes or knows that the defendant is the source of the print. When the examiner offers a weaker, but more scientifically justifiable, conclusion, the evidence is given less weight. However, people do not value the evidence any more or less when the examiner uses very strong language to indicate that the defendant is the source of the print versus weaker source identification language. We also find that cross-examination designed to highlight weaknesses in the fingerprint evidence has no impact regardless of which type of conclusion the examiner offers. We conclude by considering implications for ongoing reform efforts.


Related Resources

A thick gray wavy line forming an abstract, looping shape on a light gray background.

An Introduction to the Forensic Handwriting Analysis Software handwriter

July 18, 2025

Blue shoeprint with a tread pattern on a white background.

Forensic Footwear: A Retrospective of the Development of the MANTIS Shoe Scanning System

July 10, 2025

There currently are no shoe-scanning devices developed in the United States that can operate in a real-world, variable-weather environment in …

A green fingerprint icon on a light gray background.

Examiner consistency in perceptions of fingerprint minutia rarity

July 10, 2025

Friction ridge examiners (FREs) identify distinctive features (minutiae) in fingerprints and consider how rare these observed minutiae are in their …