BOLINGBROOK, Ill. (AP) -- Former Bolingbrook police officer Drew Peterson walked out of jail in Joliet this afternoon a short time after one of his sons posted $7,500 bail.

Earlier today Peterson turned himself in to authorities after he was charged with unlawful use of a weapon. The felony charge is related the length of the gun barrel. Authorities say the barrel is less than 16 inches long -- a violation of state law.

Peterson is a suspect in the October disappearance of his wife, Stacy. He has not been charged in the case.

Peterson attorney Joel Brodsky says the weapon is a semiautomatic assault rifle that Peterson used while he was a police officer. He contends police officers are exempt from the length provision of the law and Peterson was still a police officer when the gun was seized.

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