Samantha Karner
Official ATF toolmark examiner
ATF firearm and toolmark examiner. Defense witness at prelim. Compared the autopsy jacket fragment to the recovered rifle and reported inconclusive.
Karner testified she received fragments in a manila envelope, cleaned the largest piece, and “peeled the petals back.” Not enough microscopic marks to identify or exclude the rifle. Inconclusive is not exclusion. The same ATF shop also reported that casings from Robinson’s home had been fired by that rifle, a different comparison.