The Week 78 Forensic Science Geek of the Week is Announced

The Forensic Science Geek of the Week

Please visit the www.TheTruthAboutForensicScience.com FaceBook fan page.

The week 78 “www.TheTruthAboutForensicScience.com Forensic Science Geek of the Week” honors goes to: Steven W. Hernandez, Esquire

According to our Geek, the following is offered:

Steven W. Hernandez, Esq., is admitted to practice in State of New Jersey and the United States District Court for the District of New Jersey. He specializes in DWI defense. Mr. Hernandez is a member of the National College of DUI Defense (NCDD). American Bar Association, The New Jersey Bar Association, and the Ocean County Bar Association. He has successfully completed the DUI Detection & Standardized Field Sobriety Testing, the same course recognized by the National Highway Transportation Safety Administration (NHTSA), used to train police personnel. Mr. Hernandez was the first attorney in New Jersey to receive his Forensic Sobriety Assessment (FSA) Certificate, by demonstrating knowledge of the science and forensic use of roadside sobriety testing.

Congratulations to our Forensic Science Geek of the Week winner!

OFFICIAL QUESTION:

: Forensic Science Geek of the Week Challenge

1. What is pictured above?

2. What is it used for?

3. How does it work?

4. Are there any known issues with respect to its forensic suitability? If so, what?

Our Geek of the Week answered:

(1) Duquenois-Levine Reagent is a test for detecting marijuana and hashish and the residue of THC in paraphernalia. It contains vanillin, concentrated hydrochloric acid, and chloroform (2) It used by : a. Removing clip; b. Adding substance into pouch c. Replace clip d. Break left ampoule, agitate for one minute. Look for any color that formed (none should occur). e. Break middle ampoule, agitate until color changes. Look for any color formed (a rich violet-blue should occur). f. Break right ampoule, and agitate for 5 seconds. g. Observe color change: if slate grey upper level over purple lower level, then it is positive for marijuana. (3) Forensically speaking it is not very reliable. The test has been known to produce false positives and has been known identify some plants, such as nutmeg as marijuana.

[BLOGGER’S NOTE: The myth of specific identification of Marijuana in criminal court Part 4: What is the modified Duquenois-Levine test? Is it a “good” test?

A very honorable mention goes to: Anthaony Graviano who wrote:

1. The image is of an Duquenois-Levine reagent pouch which is part of an ODV NarcoPouch narcotics field testing kit.

2. It is used by investigators to test an unknown substance for the presence of Marijuana.

3. The test is performed by first placing approximately 10-20mg of the target substance into the ampoule that comes with the testing kit. The Duquenois-Levine reagent pouch is then added to the ampoule. The mixture is shaken to allow for a proper mixture and if the mixture turns purple it is an indication that the unknown substance is Marijuana.

4. This test has a number of known issues. There is room for error in the tester’s perception of the color. Factors such as improper lighting or the background in which the test is viewed upon could impact the tester’s perception and they might think the test turned purple when it is, in-fact not. Starting in the 1960’s and 70’s, there were various studies that indicated the Duquenois-Levine reagent test is not specific to Marijuana. In 1969, a UK government scientist named M.J. de Faubert Maunder discovered that 25 different organic substances produced a similar color as Marijuana in the Duquenois-Levine reagent test, warning that it should never be used as the only conclusive evidence. Another study which was published in 1975 in The Journal of Criminal Defense stated “The microscopic and chemical screening tests presently used in marijuana analysis are not specific even in combination for ‘marijuana’ defined in any way.” In conclusion, the NarcoPouch field testing kit is not forensically suitable to be used by itself as conclusive evidence that an unknown substance is Marijuana.

The Hall of Fame for the www.TheTruthAboutForensicScience.com Forensic Science Geek of the Week:

Week 1: Chuck Ramsay, Esquire

Week 2: Rick McIndoe, PhD

Week 3: Christine Funk, Esquire

Week 4: Stephen Daniels

Week 5: Stephen Daniels

Week 6: Richard Middlebrook, Esquire

Week 7: Christine Funk, Esquire

Week 8: Ron Moore, B.S., J.D.

Week 9: Ron Moore, B.S., J.D.

Week 10: Kelly Case, Esquire and Michael Dye, Esquire

Week 11: Brian Manchester, Esquire