AURORA, Ill. - An initial background check failed to detect a felony conviction that should have barred the man who killed five co-workers and wounded six other people at a suburban Chicago manufacturing plant from buying the gun. Months later, a second background check of Gary Martin found his 1995 aggravated assault conviction in Mississippi involving the stabbing of an ex-girlfriend. But it prompted only a letter stating his gun permit had been revoked and ordering him to turn over his firearm to police--raising questions about the state's enforcement to ensure those who lose their permits also turn over their weapons. (The Star--Aurora Shooter's Permit was Revoked but Gun Wasn't Seized, Feb.17, 2019)