What is a Ballistics Expert & What Do They Do?

April 5, 2022 Criminal Defense

Although each criminal case is different from the next, one commonality among criminal cases is that they often involve the use of an expert witness. An expert witness will use their scientific, technical, or other specialized knowledge to assist the trier of fact in reaching a decision. To read more about expert witnesses, as well as the other two kinds of witnesses in a criminal trial, visit our blog here.

One kind of expert that is often utilized in a criminal case is a ballistics expert, also referred to as a firearm or forensic ballistics expert. A ballistics expert is a forensic specialist that is responsible for the collection and analysis of ballistics-related evidence. This blog will explore the science behind ballistics expertise, how such experts perform their work, and what training is required for someone to be deemed a ballistics expert.

The Science Behind Ballistics

The study of ballistics is the study of motion, dynamics, angular movement, and effects of projectile units such as bullets, bombs, and missiles. Rooted in physics, ballistics experts will be used to determine everything from “trajectory to probable distance and angle when studying firearms and ammunition. A ballistics expert may study shell casings, bullet fragments, clips, and firearms at the scene of a crime and in laboratory testing.” If a crime scene involves ammunition, a ballistics expert will engage in ballistics fingerprinting. This process involves studying the marks that are left on ammunition in order to conclude what firearm it came from. This is possible because each firearm produces different imprints on the ammunition, resulting in each shell casing or bullet having its own unique “fingerprint.” The imprints or amount of damage a piece of ammunition has sustained can then help determine where the shooter was standing when they used the firearm and what angle the firearm was fired from. Further, any residue left on the ammunition can “be studied and compared to residue on the hand of a suspect, the gun that was fired, or any object that was close by when the firearm was used,” all of which is information that helps decipher the identity of the shooter. In addition, a ballistics expert may be retained to “identify the characteristics of firearms, from the bullets fired to calibers and rifling patterns. They also analyze cartridges and cases to search for signs of firing pin impression, ejector marks, extractor marks, and other toolmarks.” 

Evidence that a ballistics expert may examine include, but is not limited to:

  • Firearms
  • Live ammunition
  • Spent shell casings/bullets
  • Spent cartridges
  • Shotshell wadding
  • Clothing

The Process

So, how do ballistics experts examine all of this evidence? Sometimes, their work is performed in a laboratory, but they can also be brought onto the crime scene to collect, preserve, or analyze evidence. Often, ballistics experts are involved in crime scene mapping, a practice that “involves using computer design programs, photogrammetry, and laser measuring tools [as well as] create[ing] diagrams for police reports and for courtroom presentations.” Ballistics experts may also retrieve DNA samples from the ammunition of firearms they analyze by lifting the fingerprints found on them. After all of the evidence is examined, ballistics experts will create reports of their findings that can be used by law enforcement and within the courtroom.

Is Ballistics Evidence Reliable?

The question of whether ballistics evidence is reliable has caused much contention among defense attorneys and prosecutors for decades. Although ballistics are often held as indisputable science, the reliability behind the science has faced increased skepticism by courts. One prominent example is  United States v. Green, where the court held that the ballistics expert could testify that the casings in the bullets were similar, but was not permitted to conclude that they came from one specific gun, “to the exclusion of every other firearm in the world.”

Training and Educational Requirements

Although there are no specific degree programs for ballistics, many ballistics experts will have a degree in forensic sciences, which encompass the disciplines of biology, chemistry, and physics while also incorporating the study of criminal justice. However, many ballistics experts have a degree solely in criminal justice or some related science. As obvious as it may sound, the expert must also have significant experience in the world of ballistics, which may include training in the following:

  • Ammunition
  • Handling of evidence
  • Crime scene searches
  • Firearms identification
  • Gunpowder and primer residue
  • Wound ballistics
  • Microscopy

Many experts in ballistics learn about the discipline by working under the supervision of an experienced ballistics or firearms expert. In addition, many ballistics experts specialized in the field after they went through on-the-job training as law enforcement officers.

Tallahassee Criminal Defense Attorney

If you or a loved one has been accused of a crime involving a firearm, contact a qualified Tallahassee criminal defense attorney who will find a valuable expert witness to assist in your defense. Don Pumphrey and the members of the legal team at Pumphrey Law Firm have experience dealing with all kinds of criminal charges and will consult with knowledgeable expert witnesses in the field, such as the field of ballistics, so every applicable defense is explored in your favor. Call us today at (850) 681 – 7777 or send an online message today to discuss your legal matter during an open and free consultation with an attorney in our legal team.

Written by Sarah Kamide


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