PITTSBURGH—A federal judge has dismissed a former inmate's legal claims against the Pennsylvania Department of Corrections for alleged sexual abuse, but says allegations that his rights were violated by a suspended state prison guard and prison managers can proceed.

The unidentified inmate sued in 2011 and his allegations led to a grand jury investigation that also resulted in charges against the guard being sued, 60-year-old Harry Nicoletti, and three others at the state prison in Pittsburgh. Nicoletti is scheduled for a criminal trial in January but claims charges that he raped or otherwise abused child molesters at the prison "made up."

U.S. Magistrate Judge Lisa Lenihan says the state is immune from being sued for anything the guards did in their official duties, though claims against Nicoletti and since-fired managers at the prison can go forward individually.