I don't see how private sales like that can ever be regulated.But I don't think you should be able to sell your gun to a stranger at a gun show.Maybe there should be one law for all 50 states that you have to be a licensed dealer to sell at a gun show.How about the parking lot of a "gun show"?How long do you have to know someone before they are considered a "stranger"?Is a guy selling a gun at his table at a flea market considered to be at a gun show?How about having three guns on a table at a yard sale?In your quest to pass a "feel good" gun law that has absolutely nothing to do with what happened, you are overlooking the obvious,,,,