People v. Jennings
Citation and Court
252 Ill. 534 (Illinois Supreme Court 1911)
Facts
Jennings was charged with murder. The prosecution introduced fingerprint evidence — comparing prints found at the scene to Jennings’s prints — as part of its case. Jennings challenged the admissibility of fingerprint evidence, which was not yet a recognized forensic science in American courts.
Issue
Whether fingerprint evidence is admissible at trial as a reliable form of scientific identification.
Holding
Fingerprint evidence is admissible; the court found that the science of fingerprint identification was sufficiently established to be admitted, and its reliability could be tested by cross-examination and competing expert testimony.
Rule / Doctrine
Expert testimony on scientific subjects is admissible if the subject matter is beyond ordinary lay knowledge and the science underlying the opinion is sufficiently established to be of probative value. The court need not have absolute certainty about scientific reliability; general acceptance in the relevant expert community is a relevant consideration.
Significance
One of the first American cases to admit fingerprint evidence, establishing a precedent that would be followed nationwide. A landmark case in the history of forensic evidence and admissibility standards for novel scientific evidence.