Can someone honestly answer why there is still Breath testing for EtOH in America? Disclosure: As I have posted before, when people speak of Evidentiary Breath Testing (EBT) as a means of measuring Blood Alcohol Content (BAC), I shut off. My personal opinion is that: 1. The Paradigm Shift as Dr. Michael Hlastala writes is […]
Why do instruments need to be calibrated?
Calibration (and bias) schema is a procedure that imperfectly transforms a response into a useful measure. Some crime laboratories have no method or manner as to how, why or when they should calibrate their instruments. Other laboratories have truly arbitrary intervals that they calibrate their instruments, but then they declare that this arbitrary interval is […]
What is the difference between HS-GC-FID and GC-MS?
First let’s remove the short hand and really write out what we are doing typically. For blood analysis for EtOH, its proper technical name is Isothermal Static Headspace Gas Chromatography using Wall Coated Open Tubular Capillary Columns with Flame Ionization Detector. We just short name it to HS-GC-FID. The technique is made up of distinct […]
Drugs of Abuse (DOA) analysis performed today in the US
Figure 1 above: Statistics from the Substance Abuse and Mental Health Services Administration (SAMHSA) details drug use across the 50 states based on the 2006 and 2007 National Surveys on Drug Use and Health, which involved interviews with over 135,000 people around the country. (For more on the statistical breakdown of geography of non-prescription or […]
Fool’s Gold or Real Gold? HS-GC-FID is it specific or selective or neither?
So many times, Headspace Gas Chromatography Flame Ionization Detector (HS-GC-FID) is described by government expert witnesses as the “gold standard” in forensics. This trite phrase is very misleading. HS-GC-FID analysis is a very good technique when compared to other assays, but it is not infallible and it is not even the best chromatographic method available […]
How far have we come in forensic science?
There’s an old saying: “Things aren’t as bad as they used to be.” But is this true in forensic science? Eric Lander is a Professor of Biology at the Massachusetts Institute of Technology (MIT), a member of the Whitehead Institute, and director of the Broad Institute of MIT and Harvard. He currently is co-chair of […]
What can David Letterman’s Stupid Animal Tricks Teach us About Forensic Science?
What can David Letterman’s Stupid Animal Tricks Teach us About Forensic Science? One of the “types” of forensic science that is used in modern policing today is the use of specially trained canines. Canines, proponents say, can be trained for various targeted goals including cadaver search, explosive detection, drug interdiction, accelerant detection and general protection/patrol […]
You have cocaine on you guaranteed! Cocaine on Currency
You’ve got cocaine on you! YOU MUST BE A DRUG DEALER BECAUSE YOUR MONEY SHOWS COCAINE! This fun introduction is a means of relating to you the issues of the Locard Exchange Principle (https://www.thetruthaboutforensicscience.com/the-locard-exchange-principle-in-forensic-science-the-real-itouch/) as applied to cocaine and currency. It is the consensus of these works that upwards of 90-97% of paper currency in […]
The case for raw data: “Integration” in Gas Chromatography: How to make an innocent person guilty in a DUI case by manipulating the software
The case for raw data: “Integration” in Gas Chromatography: How to make an innocent person guilty in a DUI case by manipulating the software. The video below is part of the lecture that I gave at the hands-on laboratory training course held by the American Chemical Society (ACS) and Axion Analytical Labs in Chicago, IL […]
SCRAM: Sometimes the truth is a little funny
Sometimes in life things just work out to be way beyond funny…. Alcohol Monitoring Systems, Inc. markets a product they call “Secure Continuous Alcohol Monitoring” (SCRAM and SCRAMx) devices. It is perhaps best known as the Lindsay Lohan court-ordered fashion accessory. Well, it seems that SCRAM has an accessory of its own that could get […]
Lecture on Analytical Chemistry in BAC testing Part 13
The above is Part Thirteen from a lecture given by Attorney Justin J. McShane before the North Carolina Advocates for Justice “Advanced DWI Seminar”. This seminar happened on February 26, 2010. It was organized and hosted by John K. Fanney, Esquire of Fanney & Jackson, P.C. The following is a transcript of this video: In […]
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