Nonetheless he was not regarded as a problem by staff, who described him as "compliant and cooperative" and "a thoughtful, mature young man" who was "not a management problem." It appears in the isolated incident of aggression that perhaps two years of incarceration finally got the better of him, and he snapped.
He was sentenced to seven years in prison, with a non-parole period of four years. He appealed the harshness of this sentence. A review by the Appeal Court found he was a good man, with strong family support, who was unlikely to re-offend. They reduced his sentence to five years and six months, with a non-parole period of two years and nine months.
Sun was released on 13 February 2000.