The Forensic Science Geek of the Week
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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!
- 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.
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 11: Brian Manchester, Esquire
Week 12: Ron Moore, B.S., J.D.
Week 13: Ron Moore, B.S., J.D.
Week 14: Josh D, Lee, Esquire
Week 16: Christine Funk, Esquire
Week 17: Joshua Dale, Esquire
Week 18: Glen Neeley, Esquire
Week 19: Amanda Bynum, Esquire
Week 20: Josh D. Lee, Esquire
Week 21: Glen Neeley, Esquire
Week 22: Stephen Daniels
Week 23: Ron Moore, B.S., J.D.
Week 24: Bobby Spinks
Week 25: Jon Woolsey, Esquire
Week 26: Mehul B. Anjaria
Week 27: Richard Middlebrook, Esquire
Week 28:Ron Moore, Esquire
Week 29: Ron Moore, Esquire
Week 30: C. Jeffrey Sifers, Esquire
Week 31: Ron Moore, Esquire
Week 32: Mehul B. Anjaria
Week 33: Andy Johnston
Week 34: Ralph R. Ristenbatt, III
Week 35: Brian Manchester, Esquire
Week 36: Ron Moore, Esquire
Week 37: Jeffrey Benson
Week 38: Pam King, Esquire
Week 39: Josh D. Lee, Esquire
Week 40: Robert Lantz, Ph.D.
WEEK 41: UNCLAIMED, IT COULD BE YOU!
Week 42: Steven W. Hernandez, Esquire
Week 43:Ron Moore, Esquire
Week 44: Mehul B. Anjaria
Week 45: Mehul B. Anjaria
Week 46:Ron Moore, Esquire
Week 47:Ron Moore, Esquire
Week 47:Ron Moore, Esquire
Week 48: Leslie M. Sammis, Esquire
Week 49: Ron Moore, Esquire
Week 50: Jeffery Benson
Week 51: Mehul B. Anjaria
Week 52: Ron Moore, Esquire
Week 53: Eric Ganci, Esquire
Week 55: Joshua Andor, Esquire
Week 56: Brian Manchester, Esquire
Week 57: Ron Moore, Esquire
Week 58: Eric Ganci, Esquire
Week 59: Ron Moore, Esquire
Week 60: Brian Manchester, Esquire
Week 61: William Herringer, Esquire
Week 62: UNCLAIMED IT COULD BE YOU!
Week 63: Ginger Moss
Week 64: Richard L. Holcomb, Esquire
Week 65: John L. Buckley, Esquire
Week 66: Jeff Sifers, Esquire
Week 67: Josh D. Lee, Esquire
Week 68: Dr. Barbara Vonderhaar, PhD.
Week 69: Christine Funk, Esquire
Week 70: Mehul B. Anjaria
Week 71: Ron Moore, Esquire
Week 72: Mehul B. Anjaria
Week 73: Josh D. Lee, Esquire
Week 74: Kim Keheley Frye, Esquire
Week 76: Kim Keheley Frye, Esquire
Week 77: Mehul B. Anjaria
Week 78: Steven W. Hernandez, Esquire
Week 79: UNCLAIMED. IT COULD BE YOU!
Week 8o: Justin Harris, Esquire
Week 81: UNCLAIMED. IT COULD BE YOU!
Week 82: Jay Tiftickjian, Esquire