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Issues in Explosive Residue Analysis: Back to the Basics: Was it the result of an explosive device in the first place? How do we know that?

On April 5, 2012, in Explosive Residue, Trace Evidence, by Justin J. McShane

Issues in Explosives Residue Analysis A Primer for the Bar Frederic Whitehurst, Ph.D.[1] [Editor’s Note: This is a multi-part series deigned to educate the defense bar on important issues concerning explosive and explosive residue investigations] Part 1: Introduction Part 2: Back to the Basics: Was it the result of an explosive device in the first […]

Guest Blog Post From Dr. Frederic Whitehurst PhD JD: Issues in Explosive Residue Analysis

On March 29, 2012, in Explosive Residue, Trace Evidence, by Justin J. McShane

Issues in Explosives Residue Analysis A Primer for the Bar Frederic Whitehurst, Ph.D.[1] [Editors Note: This is a multi-part series deigned to educate the defense bar on important issues concerning explosive and explosive residue investigations] Part 1: Introduction Part 2: Back to the Basics: Was it the result of an explosive device in the first […]

Guest Blog Post From Dr. Frederic Whitehurst PhD JD: On sampling when testing multiple packets

On February 23, 2012, in Chemistry, Identification, Laboratory Procedure, SANE / Safe Nurse Examination, Trace Evidence, by Justin J. McShane

Sampling Crime: On sampling when testing multiple packets By: Frederic Whitehurst, J.D., Ph.D. [1] If we accept that forensic crime laboratories are completely overwhelmed, understaffed, underequipped, and exhausting environments in which to function, we see reality. Despite political rhetoric to the contrary, there has been little, if any, relief for those folks in crime labs […]

Guest Blog Post From Dr. Frederic Whitehurst PhD JD: “Matches” An Over inference of Data? A Giglio Obligation? The case of Paint Examination

On February 9, 2012, in Chemistry, Contextual Bias, Ethics, Ethics: Scientist, Identification, In The Courtroom, Paint Analysis, Trace Evidence, by Justin J. McShane

“Matches” An Over inference of Data? A Giglio Obligation?: The case of Paint Examination By: Frederic Whitehurst, J.D., Ph.D. [1] and Darlene R. Brezinski, Ph.D.[2] Forensic chemical analyses of complex matrices such as plastics, paints, or paper products, may lead to inconclusive results without analysts or reviewing counsel aware of the failing of the analyses. Complex […]

What can David Letterman’s Stupid Animal Tricks Teach us About Forensic Science?

On December 21, 2010, in Equipment, Identification, In The Courtroom, Trace Evidence, by Justin J. McShane

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

On December 16, 2010, in Chemistry, Crime Scene Investigation, Equipment, Trace Evidence, by Justin J. McShane

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 […]

Excercise of Discretion: Sampling versus Sample Selection

On October 5, 2010, in Crime Scene Investigation, Ethics, Ethics: Scientist, Forensic Discipline, Identification, In The Courtroom, Laboratory Procedure, Trace Evidence, by Justin J. McShane

One of the most shocking aspects of forensic science to me as I am not a scientist is the amount of discretion and choice that is exercised by the forensic analyst. One of these areas is the difference between sampling and sample selection. A good analogy to use is to suppose that you are tasked […]

DNA Contamination that is amazing!

On August 10, 2010, in Crime Scene Investigation, DNA, Ethics, Ethics: Scientist, Identification, Trace Evidence, by Justin J. McShane

This is the Phantom of Heilbronn. The Phantom of Heilbronn was thought of as the most prolific murderer who was allegedly responsible for a whole rash of crimes from murder to burglary. Quite a busy person. So, busy that the Phantom was all across Europe doing what the Phantom does, I suppose, which is getting […]

What constitutes a “match” in forensic science?

On June 1, 2010, in Ballistics, Crime Scene Investigation, DNA, Forensic Discipline, Forensic Firearm and Toolmark Analysis, General Information, Identification, In The Courtroom, Laboratory Procedure, Pattern Recognition, Trace Evidence, by Justin J. McShane

The concept of a match at first look blush seems rather elemental. However, if we really were to think of it, the concept is indeed fungible. In forensic science, there is no universally held definition across all disciplines or even within a disciple as to what constitutes sufficient similarity to evoke that coveted and magic […]

The Locard Exchange Principle in Forensic Science: The real iTouch

On April 22, 2010, in Crime Scene Investigation, General Information, Trace Evidence, by Justin J. McShane

“Every contact leaves a trace” is how the Locard Exchange Principle which is really a hypothesis is summarized. It has been written as follows: Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as a silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibers […]

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