receipts from a local gun store supported george kerr's claim, that doug gustafson had bought an hk-91the day of the murder. kerr also said that he, cheely, and gustafson had been shooting the gun earlier that day, and they used a road sign as a target. investigators found that sign with three bullet holes. to test kerr's story, investigators turned to forensic analyst robert shem. he test fired an hk-91 into a piece of metal the same thickness as the road sign. then using a rubber-like casting substance called microsil, he made impressions of the bullet holes in the road sign and those produced by his test firing of the same type of gun. the castings were compared under a microscope. >> once i removed the rubber, i was able to establish that the holes in the sign were indeed 0.30 caliber, and they possessed the same rifling characteristics as an hk-91. >> the test proved kerr's claim that the boys were using an hk-91 that day. but could investigators prove the shooting was intentional? the fatal bullet entered the car through the back window, hit the victim, and exited through the pas

. >>> about a year after the highway shooting, a package was mailed to george kerr in care of his family's address in eklutna, alaska. since george was out of state, his father decided to open it. 44-year-old david kerr was killed instantly. george's stepmother michelle was barely alive.