Citation

Poupko JM, Hearn WL, Rossano F. J. Forensic Sci. 2018; 63(5): 1340-1345.

Affiliation

Cognitive Science Department, University of California San Diego, La Jolla, CA, 92093-0515.

Copyright

(Copyright © 2018, American Society for Testing and Materials, Publisher John Wiley and Sons)

DOI

10.1111/1556-4029.13755

PMID

29495067

Abstract

Several studies have reported on wide-spread contamination of U.S. paper currency with cocaine and to a lesser extent other illicit drugs. Canines are trained and employed to search for and alert to drugs. Canine alert to currency has been used as evidence that currency has been directly involved in illicit drug trafficking to justify currency seizure and forfeiture. This assertion, particularly when the only evidence is based upon canine alert, has been challenged in the courts considering that most currency in circulation is contaminated with cocaine. Comprehensive review of the scientific literature establishes that (i) 67-100% of circulated U.S. currency is contaminated with cocaine ranging from a few nanograms to over one milligram/bill (ii) various biological and environmental parameters impact canine alert to drugs. It is concluded that canine alert to U.S. currency is not sufficiently reliable to determine that currency was directly used in an illicit drug transaction.

© 2018 American Academy of Forensic Sciences.

Language: en

Keywords

canine alert; cocaine; critical review; currency contamination; forensic relevance; forensic science