A judge has described the Taranaki father who killed his son for money as a cruel man with no remorse for his actions.
Opunake man David Roigard was sentenced to life in prison today, with a minimum non-parole period of 19 years for murdering his son, Aaron.
He was also sentenced at the New Plymouth High Court for eight charges of theft in a special relationship for stealing his life savings, to be served concurrently.
Roigard was arrested six months after Aaron went missing in June 2014.
It's believed the 27-year-old discovered his father had been spending a large percentage of his salary, which he had been entrusting him with, to put in a trust, and he confronted him about it.
Aaron and his partner, Julie, who were both farm workers, believed the money was going towards buying their dream farm.
Aaron's body has still never been found, with the Crown arguing during the trial in December that it is buried high up in south Taranaki farmland.
Despite the lack of a body, Roigard was found guilty of the murder as well as eight charges of theft in a special relationship for whittling away Aaron's life savings.
In sentencing, Justice Paul Heath told Roigard it was "chilling" that he showed no remorse for the killing.
"You do not accept responsibility for what you did. You show no remorse, you show no understanding of the enormity of your deceit and the evil act of killing your own son."
He also described Roigard as a cruel, compulsive liar.
"Parents are there to support and protect their children. No father should steal from his son. Certainly, no father should deliberately kill his son."
He says Aaron trusted his father, who betrayed him.
The officer in charge of the murder investigations says police have still got unfinished business, even after Roigard was handed a lengthy prison sentence.
Detective Senior Sergeant Blair Burnett says they're still doing everything they can to find Aaron's body.
"We have a conviction; we don't have a body. My frustration levels are high. They've always been high. It frustrates me that the man doesn't have the decency to tell us where his son is."
A detective visited Roigard in prison and tried to get him to give up the location of the body, but he remained silent.
"We'll regroup, we'll look at what we've done and we'll look at the bigger picture and work out whether we may have missed something or not, whether there's something else we can do.
"At this point in time, there's nothing further to search or places to search, but in light of any credible information we'll reconsider and carry on.
"I made a promise at the start that we'd bring him home and that stands."
But Det Snr Sgt Burnett says as time goes on, he becomes less positive about finding the body.
"I think that's a fair reflection of what we're doing. It's more and more difficult with the passage of time to find somebody, especially in the ruggedness of south Taranaki and Mt Egmont. It's a vast, rugged place and without the help of David, and if someone does know, I'm not that positive."
Aaron was last seen at his father's Waiteika Rd home in Opunake on June 2, 2014, and extensive land, sea and air searches have failed to locate a body.
Aaron's partner, Julie Thoms, previously told Newhub she and their two young sons had been left with nothing, as she quit her job thinking they were moving to their new farm.
She said she would never forgive Roigard.