Gunshot Residue Creates an Impression

Gunshot residue or GSR is an important component to any homicide crime scene involving the discharge of a firearm. It tells a story. The big question is how accurate is the story and is it retold correctly. As they say, some evidence may not be what it seems. The best place to start is at the beginning of course.

First, a little background on GSR. What exactly is it? GSR is categorized as trace evidence and it is made up of the compounds lead, barium, and antimony. When someone fires a gun the...