Drug Laws in New Jersey: The Frailities of the Duquenois-Levine Field Test

For over seventy years the Duquenois- Levine Test (DLT) has been used as a field test by law enforcement agents to identify controlled dangerous substances. (CDS).  Recent studies have shown that the DLT can provide a false positive result to eucalyptus, patchouli and cypress, as well as Hershey’s Dark Chocolate Kiss and various other chocolate products.

Another other test known as the KN Reagent Test, which is also used as a field test by law enforcement agents can provide false positives for many herbs including thyme, oregano, anise extract, ginseng, vanilla and peppermint.

Most good criminal lawyers are aware of the frailties of these field tests and maintain a careful watch over cases were the underlying arrest was precipitated by the use of these test.