 He also told the therapist that he estimated that he had raped 13 younger boys by the time he was 16.In 1980, also in Tacoma, Duncan stole a number of guns from a neighbor and then abducted a 14-year-old boy and raped him at gunpoint.Duncan was sentenced to 20 years in prison for this crime, but was released on parole in 1994 after serving 14 years.