Terminology in Forensics: Its Use and Abuse
Written by Edward E. Hueske   

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IN THE 25-PLUS YEARS that I have been teaching shooting-incident reconstruction classes to police agencies, I have fought what seems to be a losing battle to promote the use of proper terminology regarding firearms, ammunition components, and related areas by field investigators and others in written reports and court testimony. An apparent difficulty in overcoming deeply ingrained misapplications of terminologies and colloquialisms has pervaded. The situation is perpetuated from training officer to trainee and on to succeeding generations of trainers/trainees. Reinforcement of improper terminology via the media is a 24/7 matter.

What exactly are we talking about? Some of the more commonly misused terms include “clip” when referring to magazines, “projectile” as a catch-all term for both intact bullets and fragments thereof, and the most commonly abused term of all: referring to a cartridge as a “bullet”. Firearms examiners are the source of the appropriate terminology.

So what’s the big deal, anyway? The big deal is that when improper terminology is applied to evidentiary items, confusion is frequently introduced that can make it difficult or even impossible to interpret the case at hand. That dictates the additional expenditure of time and energy to decipher. For example, when all the intact fired bullets, fired bullet fragments, bullet cores, and bullet jacket fragments from a shooting scene/autopsy are packaged and the contents collectively labeled as “projectiles”, no one either reading the associated evidence inventory or the crime scene report has a clue as to what was actually collected. That necessitates opening packages in order to determine the contents of each.

Some might argue that when the firearms unit evaluates the evidence, they will sort it out and describe it appropriately. Unfortunately, such evidence is not always sent to the firearms unit for a variety of reasons. Also, if the crime scene investigator who introduces the evidence at trial refers to everything as a “projectile”, confusion develops when the firearms examiner testifies and uses different—albeit proper—terminology. A related problem frequently encountered in court is that prosecutors use the same improper terminology that the firearms examiner is trying to overcome in his or her testimony, leaving the jury lost in a cloud of multiple terms.

So what is the solution? The solution is for everyone in the evidence chain of custody to use the correct term for each item collected. To use the correct terminology in all associated documentation. To use the correct terminology in departmental policies and procedures. To use the correct terminology in press releases, news conferences, interviews, and court testimony.

The following glossary lists and describes the most frequently “abused” terms. The fundamental principle to keep in mind is simply: “Call it what it is and be as specific as possible.”

Bullet—The projectile portion of a cartridge typically consisting of either lead, electroplated lead, or a lead inner core with a copper or brass skin (jacket).

Fired bullet—Bullet with obvious signs of firing (i.e. rifling marks and/or damage/expansion).

Bullet core—Inner lead core from which the jacket has separated. There will be no rifling marks present on the core, only on the jacket.

Bullet jacket—The copper or brass outer skin of a jacketed bullet. Fired bullet jacket will have rifling marks and damage/expansion visible.

Fragments (i.e. bullet fragment, jacket fragment, core fragment)—Obviously incomplete based upon size and appearance.

Shot pellets—May be visibly damaged; if so, describe as such.

Slug—Lead projectile designed to be fired in a shotgun. Since there is typically no rifling in a shotgun barrel, the slug will frequently have rifling cast into it to impart spin stabilization.

Unidentifiable metal fragment—Metallic fragment having no discernible bullet/pellet/slug characteristics. If the surface can be indented/scratched with the thumbnail and is dark gray, it is reasonable to refer to it as an “unidentifiable lead fragment”.

Cartridge—A complete (unfired) unit consisting of a cartridge case, powder charge, bullet, and primer (either rim-fire or center-fire).

Cartridge case—May be fired (as indicated by firing pin impression and interior soot deposits) or unfired. Be specific in your description.

Shotgun shell or shot shell—If fired, there will be a firing-pin impression and an open end absent of powder/pellets/slug. Correctly referred to as “fired shot shell”.

Shot cup—Plastic component that holds the shot.

Wad—Plastic, paper, or fiber disk that separates the powder from the shot.


Fired cartridge cases


Clockwise from bottom: Fired shotgun shell, buckshot pellet (copper plated), shotgun slug, fired bullet, fired bullet (jacketed), buckshot pellet (unplated)


Fired jacketed bullets

A related area where inappropriate terminology and misunderstanding often produces confusion is gunshot residue, collectively referred to as GSR. The misunderstanding comes as a result of the reality that “GSR” actually includes two very different components: (1) Gunpowder residue and (2) primer residue. As a case in point, I recall testifying a number of years ago about a shooting incident. I was being cross-examined by opposing council and was asked the question, “Did you test for GSR?” My response was, “What type GSR are you referring to sir?” The attorney had no idea how to respond so he said, “The usual kind.” This lack of understanding is not uncommon, even with police investigators.

The following terminology appropriately defines the components of gunshot residue or GSR:

GSR—General term that includes gunpowder residue and primer residue. (One really must make the distinction as to which is being referred to.)

Powder particles—Visible residue on clothing or other inanimate articles.

Powder stippling/tattooing—Abrasions (not burns!) on skin produced by gunpowder impact. Post-mortem stippling appears yellow-brown as opposed to the reddish color of ante-mortem stippling.

Primer residue—Deposits of ultra-microscopic spheroid particles containing compounds of barium, antimony, and lead that result from firearms discharge.

Soot deposits—Dark residue (“smoke”) resulting from gunpowder combustion (discharge).

Bullet wipe—Black soot or grease ring at the margins of bullet holes through inanimate objects.

Admittedly, many of the terms presented here are not familiar terms that are part of the everyday vocabulary of the general public. But, these terms need to be learned and utilized by members of the criminal justice community. The time spent learning the appropriate terminology would likely be easily offset by the saving of time lost trying to decipher confusion as to what the evidence actually consists of, to say nothing of the elimination of confusion generated during court testimony. The glossary should also be part of the required reading for members of the media.


About the Author

Edward E. Hueske has spent 40 years as a practicing forensic scientist, including 23 years with government crime labs in Texas, Oklahoma, and Arizona (retiring in 1996), and 14 years as a full-time faculty member in the department of criminal justice at the University of North Texas (retiring in 2012). He currently consults with prosecution, defense, and police agencies in civil/criminal matters and provides training to police agencies in shooting incident reconstruction. He is the author of Practical Analysis & Reconstruction of Shooting Incidents (CRC Press 2006), Fingerprints & Firearms (Facts on File 2008), and numerous articles published in various forensic journals. He is a fellow of the American Academy of Forensic Science, Emeritus Member of the American Society of Crime Laboratory Directors, Emeritus Member of The Southwestern Association of Forensic Scientists, and Distinguished Member of the Association of Firearm & Tool Mark Examiners.

 

 
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