The dogged campaign by antigun-violence advocates like those at CeaseFirePA, and the national group Mayors Against Illegal Guns, for tighter controls on tracking weapons - with corresponding penalties for gun owners who fail to report missing weapons - is aimed at stopping straw buyers from funneling legally purchased weapons to felons and others barred by law from owning a gun. (That would include the mentally unstable, a safeguard seen as ever more critical in light of recent mass shootings at the Connecticut school, a Colorado theater, and elsewhere.)