Jackson, Mississippi Criminal Defense Lawyer On Gunshot Residue (GSR)

For crimes that involve the use of a firearm, gunshot residue (GSR, for short), can play a major role in determining who committed the crime.

What is Gunshot Residue?

When a gun is fired, hundreds of nearly invisible particles are blown backwards toward the shooter.  The particles consist of lead, barium and antimony.  The combination of these particles is gunshot residue.  When the particles are expelled backwards, they stick to the shooter’s hands.

Where is GSR typically found?

In the case of a shooter, GSR is usually found on the thumb and index finger, including the “webbing” that connects the thumb and index finger.  GSR is sometimes also found as far back as the wrist and lower arm.

How do the Police find Gunshot Residue?

To collect gunshot residue, police use a small, round tube-like device.  The tube is approximately one and-a-half inches long.  One side of the tube is a plastic piece, which has a metal “mount” on the inside.  The mount has an adhesive covering.  This side is referred to as the stub.  The other side of the tube is simply a clear plastic covering.  This side is called the holder.

When police want to collect gunshot residue, they will have the person hold out each hand.  They will take the collection device and remove the holder from the stub.  Then, police will take the stub and touch the mount over the areas of the hand they wish to test.  If there is GSR on the hands, it will stick to the adhesive on the mount.  Once this is completed, the stub is placed back in the holder and is sent for GSR testing.

How long does GSR stay on the hands?

Not very long.  Studies have shown that a hard slinging or shaking of the hand will scatter some of the particles.  If the hand is rubbed against clothing or wiped with a towel, there’s a good chance that most, if not all, gunshot residue will come off the hands.  If the hands are washed, GSR is most likely gone.

It’s also possible for the police to inadvertently remove gunshot residue from a suspect’s hands during handcuffing.  When an officer handcuffs a suspect, the GSR can be transferred from the suspect’s hands to the handcuffs, and even to the officer’s own hands.

The more time that is placed between the GSR being deposited on the hands and the time the test is performed, the more chance there is for the residue to disappear.

What does the presence of gunshot residue prove?

Viewed by itself, the presence of gunshot residue simply proves that a person’s hand has come into contact with gunshot residue.  Period.

But, when the presence of GSR is viewed along with other evidence against a suspect, it can make a fairly tight case that the person committed the crime.

What does the presence of GSR not prove?

The presence of GSR does not conclusively prove that a person fired a gun.  This is because the mere presence of GSR does not prove how the GSR got on the hands in the first place. 

It’s true that gunshot residue is most likely deposited when a person fires or handles a recently fired firearm.  However, there is at least a likelihood that GSR can be transferred by touching another person who has GSR on his hands, or by touching a surface (such as a body) that has residue on it (close-range gunshot wounds have residue deposits around the entry wound).  These are less probable explanations, but must be kept in mind before thinking GSR is the literal “smoking gun” in a crime.

Forensic evidence is a part of every violent crime.  I’m fortunate to have been law enforcement trained in forensic evidence, including the collection of gunshot residue.  If you’ve been charged with a violent crime, you need a tough Mississippi criminal defense attorney with a thorough knowledge of forensics.  Please contact me to discuss your case.

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7 responses to “Jackson, Mississippi Criminal Defense Lawyer On Gunshot Residue (GSR)

  1. if your firing a weapen up close what is the gun shot residue called

  2. Victim shot with shotgun, #8 shot, 12 gauge, distance 2ft, no gunshot residue—WHY?

  3. None on the victim.

    It was said that the shot was through a beer can rammed over the barrel of the gun. Also, I have heard that silk material over the muzzle can absorb powder residue. Although, the wad and pellets were in the victim.

    Please comment. Thank you.

  4. Anything that is touched by the blast or the pellets themselves could absorb some of the residue. However, it is hard to believe that ALL the residue would be absorbed, especially at a distance of 2 feet with a blast as forceful as a shotgun.

    The absence of GSR causes me to question whether the distance estimate is correct.

    How did investigators calculate the distance? GSR is normally used to determine distance, but there was none in this case. Did they use the dimension/type of entry wound, witness statements, defendant’s confession?

    Something isn’t quite adding up.

  5. This is merely a part of the mess of a case I investigated many years ago that was slopped up so bad at the beginning of the investigation by law enforcement that it became an impossible quagmire.

    A guy has been found guilty by a jury due to a small amount of DNA collected under the victims fingernail, which was the accused girlfriend at the time and they lived together up til her death. That small amount of DNA was circumstansial evidence.

    Another guy and I are trying to reinvestigate.

    It is my understanding that the MO crime lab estimated the shotgun barrel being approx. 20″ from the victim when discharged deducting it was the dimension/type of entry wound.

    The following is a couple of paragraphs from the “Pathologic Diagnoses”:

    “Shotgun wound of neck: Located on the right side of the neck is a shotgun wound located 10″ inferior to the top of the head and 2.25″ rt of midline. The defect measures 3.50″ X 2.50″ and is 1.50″ deep. There is no gunpowder residue surrounding or in the depths of the wound.”

    “Path of the bullet: After entering the skin, the shotgun pellets destroy the underlying soft tissues, musculature and all of the great vessels on the rt side of the neck. There are multiple fragments of the cervical vertebral column exposing the spinal cord. There are pellets located deep within the wound and on the front of the cervical vertebral column. Recovered are approx. 15 shotgun pellets of approx #6-7 shot size and a shotgun wad. Also recovered are two fragments of yellow metal of undetermined origin.”

    The body laying in the open may have been exposed to a light rain for an hour or so. We don’t know????

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