Friends of Donald W. Matthews, a 61-year-old former Steelworker who quoted the U.S. Constitution like a preacher thumbing a worn Bible, say he was suspicious of government.But nobody knows why he chose a routine traffic stop Friday night to make his final stand, fatally shooting a Massillon police officer in the back before he was killed himself in return gunfire.He might have been returning home from a constitutionalist study group in Cleveland when a state trooper pulled him over for speeding.The trooper stopped him near Edwards Road in the short stretch of state Route 21 that crosses Wayne County. It...