Peterson, 54, who gained nationwide attention after the disappearance of his fourth wife, Stacy, in October 2007, was arrested after a warrant was issued on one of the 11 guns seized during a search of his home after Stacy's disappearance, according to his attorney Joel Brodsky.
Police claim the rifle barrel was too short under Illinois law. But Brodsky says Peterson is exempt from the provision because he was an officer when the weapon was seized.
Authorities are also investigating the death of his third wife, Kathleen Savio – whose 2004 drowning was ruled an accident.
– Janet Murphy