A convicted sex offender faces felony charges after lawmen learned he was being allowed to baby-sit children.The offender, Billy Clarence Martin, 56, was bound to the grand jury on charges of unsupervised contact with minor children and failure to provide a current address to the state sexual offender registry. He is being held under $50,000 bond at Warren County Jail.His charges were brought after sheriff’s investigator Jason Rowland learned Martin had been less than truthful with him when he reported in, which is required for all sexual offenders on the state registry. Martin is on the registry for a 1985 rape conviction.