WA: How Crime Labs Trace Cartridge Cases

SEATTLE – Every shell casing found at a crime scene can be a crucial piece of evidence for detectives working to match a bullet to a gun. Caleb Conn works at the Washington State Crime Lab in Seattle and says, “This is what an unfired cartridge would look like. When you fire it, the bullet will go out, go downrange, whatever you’re aiming at. What’s left is the fired cartridge case. A lot of people refer to this as the brass or the shell casings.”

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