Law-enforcement officials also are investigating whether Duncan , who committed his first sexual offense at the age of 12 , can be tied to other crimes , according to CNN affiliate KTLA in Los Angeles , California . David Duncan committed his first sexual assault at the age of 14 . He was sentenced to death last August for the killing a 9-year - old boy . He could be sentenced to death a second time if convicted again .
David Duncan committed his first sexual assault at the age of 14 . He was sentenced to death last August for the killing a 9-year - old boy . He could be sentenced to death a second time if convicted again .