Convicted murderer Phillip John Smith has a string of convictions including extortion and aggravated robbery.
In 1996, Smith was imprisoned for killing the father of a boy he molested. He was also convicted of molesting the boy over a three-year period.
Smith stabbed the 35-year-old Wellington man 19 times as he tried to protect his son, 13.
The man was never named, to prevent identification of his son.
Smith was sentenced in April 1996 to two-and-a-half years in prison for extorting money from an Auckland businessman the previous year.
The man committed suicide after receiving a letter from Smith asking for $25,000.
Smith had said if he did not get the money he would make public sexual misconduct allegations about an affair the man was having with another man.
Smith amassed 20 convictions in the five years before being sentenced for extortion and being found guilty of murder, aggravated robbery and six sexual offences.