David Benbow has been sentenced to life with a minimum period of 17 years behind bars for the murder of Michael McGrath.
McGrath disappeared almost seven years ago and despite Benbow being convicted of his murder, no body or weapon has ever been found.
Arriving at the Christchurch High Court on Tuesday, Benbow, 55, waved to his family sitting in the public gallery as he awaited his sentencing.
The former corrections officer was found guilty of McGrath's murder after two trials at the Christchurch High Court in 2023.
With McGrath still missing, prosecutors relied on several threads of circumstantial evidence for their case.
The Crown alleged he shot McGrath at his home and then disposed of the body along the Banks Peninsula.
The Crown's key argument was that Benbow's ex-partner and mother of their two children Joanna Green had started a romantic relationship with McGrath. Crown prosecutor Barnaby Hawes suggested Benbow acted out of jealousy and anger towards the new relationship when he killed him.
Hawes sought a minimum of 17 years in prison for the murder, claiming the case fits into the category of murder cases that are "especially bad" due to the "calculated level of planning" in its execution.
Defence lawyer Kirsten Grey did not accept the Crown's submission, telling Justice Eaton while the jury accepted Benbow killed McGrath, it is unclear whether they accepted the Crown's argument that there was planning involved.
Grey pointed to the fact Benbow had no prior convictions and did not have a history of violence.
"The act of murder is utterly out of character for Benbow," she said.
Justice Eaton said he believed Benbow's murder had a "heightened degree" of premeditated planning that spanned over days. He added it was an "execution style" murder.
Justice Eaton said Benbow continuing to claim he is innocent and withholding information on McGrath's body shows a lack of remorse.
"You continue to portray yourself as a victim," Justice Eaton told Benbow.
McGrath's family and partner all described the pain of not knowing where McGrath's body is to the court on Tuesday.
They delivered impact statements to a full public gallery as Benbow sat with his back to the four speakers. He never turned to look at them, instead staring towards the judge with a blank face.
Was he alone? Was he cold? Did he suffer in his final moments? – all questions that remain unanswered for McGrath's family.
His brother Simon McGrath told the court of the "harrowing" and "endless" search for his brother.
"The joy of life had simply disappeared out of view and I was not the same person," he said. "The scars, although not always visible from the outside, remain."
His mother Adrienne McGrath said she spends nights worrying her son is all alone and cold. She told the court she imagines him walking through the front door and finds it hard to believe that her son will never come home again.
Adrienne then addressed Benbow, asking him "does this mean nothing to you?"
"You still get to live your life… you had choices, you didn't have to take that path."
She said her family has been given the "life sentence of loss".