A convicted sex offender who failed to update his information with authorities as required by law was sentenced today to 15 to 30 months in prison.

Butler County Judge William Shaffer sentenced Troy A. Pett, 46, of Butler Township for failing to comply with sexual offender registration requirements.

However, Shaffer agreed to allow Pett to serve his time in the county prison rather than state prison.

Pett was given credit for already having served 420 days in the county prison.

The latest case against Pett came after he turned up missing in October 2011 from his Ravenhurst Lane home in Butler Township

Under the state’s version of Megan’s Law, Pett, who is a court-deemed sexually violent predator, must register his home address with state police and notify authorities when he moves or changes jobs.

He is required to register the information for the rest of his life.