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NEWS | May 21, 2019

Fighting crime one shell casing at a time

By Maj. Thomas Piernicky 4th Sustainment Command (Expeditionary)

She steps onto the grass in front of the house, careful not to disturb any evidence of the crime scene. Her bright yellow shirt stands out among the dark uniforms of the police near-by. Bullet casing litter the lawn in the afternoon sunlight. She examines the bullet holes in the house, the groups of different shell casings on the lawn, using science to reconstruct the scene of the attack.

The yellow shirted woman is Carolyn Fernan, a forensic firearm and tool mark investigator with the Corpus Christi Police Department. She is conducting forensic analysis of a shooting where several criminals shot up a house trying to kill a male occupant. In the ensuing gunfire, several women and small children in the house were injured. Within minutes, she gives the lead detective her analysis of the crime scene.

Fernan’s rare skills are critical to solving violent crimes in this coastal region. Her years of training and experience are invaluable to solving crimes. Nearly two thirds of the homicides in Corpus Christi involve firearms and it is Fernan’s duty to test each firearm and shell casing to help detectives match weapons to crimes or criminals.

“As a firearm examiner, for all firearms, I examine them for function and safety,” said Fernan. “In addition to that, I do trajectory analysis shooting scene reconstruction.”

“If a crime scene was a shooting and there's casings and bullets at the shooting, then I can take the question casings and bullets that are at the shooting, compare them to known samples that from a test fired firearm, and see if they match to a unique firearm or one particular firearm,” said Fernan.

Local law enforcement officers rely on Fernan’s skill set to assist them in solving crimes. Officer Michael Pernell of the Robstown Police Department has worked with Fernan on cases where her skills cut down the time required to make an arrest.

“We worked several cases together and she's sped up our clearance time exponentially versus going to the state,” said Pernell.

“We usually have to go to the Department of Public Safety, which can take months and months, which stalls your case,” said Pernell. “Having a good working relationship with her, she's able to expedite some of our more critical homicide cases and we're able to get evidence back to put towards the case file to send the case off to the district attorney's office quicker.”

With homicide cases, time is of the essence to find the murderer and take them off the street. After law enforcement shows up to a crime scene, they collect the evidence and get it to Fernan within several hours. Once the firearm and evidence are in her hands, she starts her scientific process.

“It really doesn't take that long, some guns actually mark very well,” said Fernan. “With these markings, I can get it up on a microscope, and I can match them up. Maybe the whole process takes an hour to work up the gun to go test fire to match it to the casing.”

Getting the skills to make quick turn-around in criminal investigations took years of schooling to refine. However, it was the encouragement of a friend that got Fernan on the path of law enforcement.

“Originally when I was in Army, I was finding out that physical therapy wasn't my path,” said Fernan. “I was stationed at Walter Reed and a friend of mine and I kept going to these forensic nights at the Smithsonian. And she's like, “Oh, did you know there's a forensic program at George Washington University,” and I'm thinking, you know this was like real stuff you could actually really do it.”

Fernan applied to George Washington University the next week and started classes four months later.

After getting her second degree in forensics, Fernan rejoined the Army as a police investigator where she attended the Army’s 10-week investigation school. Once she completed serving for a couple years, Fernan transitioned to the Army Reserve as a human resources officer.

Upon returning to the civilian workforce, Fernan was hired by the Corpus Christi Police Department and spent three years as a crime scene investigator. Having worked dozens of cases, she was selected for specialized training.

“I was chosen one out of 12 people in the whole United States, so we went to the National Firearms Examiner Academy,” said Fernan. “It was a one-year-long program and was taught by ATF at their national lab, Maryland.”

During that year, Fernan wrote papers, went on manufacturing tours for tools, ammunition, and firearms museums. After graduating from the program, she passed a 300-question test on firearm examination and crime scene investigation to get licensed in firearm tool mark analysis.

Thirteen years later, Fernan is considered an expert in her field and her specialized skills assist not only local law enforcement but also federal agencies to include the DEA, ATF, FBI and Homeland Security. Working out of an accredited facility assists local and federal agencies build their case against people accused of criminal activity.

Officers like Pernell are grateful to work with Fernan as her expertise helps them close cases.

“We know our standard is to prove beyond a reasonable doubt,” said Pernell. “Having that expert testimony and forensic science being conducted, and those lab results coming out of an accredited facility, like hers, really is a credit to us when we present our case to juries. We could have a slam dunk case, but if you can't convince a jury, then your case is going to go nowhere.”

With the contributions she makes to helping her fellow law enforcement officers, Fernan loves her job.

“It's the best job in the world and it's the only job that I ever want to do now” said Fernan.

For those seeking more information about the U.S. Army Reserve and how to become a Citizen-Soldier, please go to

The 211th Regional Support Group is part of the 4th Sustainment Command (Expeditionary). The 4th ESC is made up of Soldiers, civilians and their families in units headquartered throughout Texas, New Mexico, Arkansas, Oklahoma and Louisiana. As part of America’s Army Reserve, these units are trained, combat-ready and equipped to provide military and logistical support in any corner of the globe.