You're listening to the A-Pair Affair Murder Trial of Branton Vanfield from True Crime today on the Hidden Killers podcast.

Now, back to the courtroom.

Good afternoon.

Good afternoon.

Could you please state and spell your name for the court record?

My name is Kara McCarthy, C-A-M-C-M-C-C-A-R-T-H-Y.

And what is your occupation?

I am the supervisor of the Fireman Toolmark section at the Virginia Department of Forensic Science,

the Northern Laboratory in Manassas.

And how long have you been employed by the Department of Forensic Science?

For almost 12 years. And for how long have you been assigned to the forensic firearm and toolmark

section? The entire time. What is firearm identification and analysis? Firearms identification has a

primary concern to determine if a bullet, a cartridge case, or other ammunition component was fired from a particular firearm.

And how is firearm identification possible?

Firearms identification is possible because most manufacturing processes involve the transfer of rapidly changing microscopic markings onto various tool

surfaces like firearm parts. And these firearm parts may impart markings onto ammunition

components when they come in contact with each other. And then I can evaluate these markings

on ammunition components in the laboratory using microscopy.

And where did you work before you worked for the Virginia Department of Forensic Science?

I was previously employed as a firearm and toolmark examiner with the Georgia Bureau of

Investigation Division of Forensic Sciences in Decatur, Georgia.

And could you please describe your duties as a forensic firearm and toolmark examiner?

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