In the High Court at Auckland, both Andrew Parry Nicholson, 25 and John Grant Cuthers, 29, were sentenced to life imprisonment. Nicholson must serve at least 17 years and Cuthers at least 13.
Mr McMurdo's body was found by his daughter and ex-wife three days after he is believed to have died in the early hours of July 27, 2011 his daughter's 12th birthday.
Nicholson and Cuthers were trying to steal electronics from Mr McMurdo's home, south of Helensville, when they killed him violently.
Justice Graham Lang said exactly what happened would never be known but Mr McMurdo suffered blows to the head and fractures to the neck. He could have survived had medical help been sought.
Instead he was left lying in the backyard as Nicholson and Cuthers gathered his belongings to sell.
Crown prosecutor Kieran Raftery said Nicholson delivered the violence and was "the brawn". Cuthers, "the brains", ran a drugs operation but had not delivered any blows.
The pair had earlier visited the property to sell Mr McMurdo methamphetamine, but the deal fell through. So they returned to seek revenge, the Crown says.
Nicholson's lawyer Marie Dyhrberg said her client always accepted he was responsible for Mr McMurdo's manslaughter and was not seeking to walk free from court.
She questioned the painting of Nicholson as a henchman, saying he had no history of violence.
"He's been labelled because he's big but there's no evidence that he's somebody who goes there to beat up people on behalf of Mr Cuthers."
Cuthers' lawyer Lester Cordwell said his client felt shame and regret for his actions. He was now clean of drugs and looked back "with almost disbelief" to that time in his life.
McMurdo's father Bruce McMurdo read a victim impact statement to the court where he said he worried about the impact on his granddaughter. Meanwhile his wife Sue had become withdrawn from society.
"I stand here before you today talking about what can only be described as a parent's worst nightmare.
"How does one live with the fact that their youngest child has been taken from them in such a horrific and violent manner?"
Bruce McMurdo described his son as respectful, although his life hit a rocky patch in his final few months as he become involved in the drugs world.
"The old saying of 'time heals wounds' is a fallacy. This wound is one that will never be healed and is one that we will carry on our shoulders for the rest of our lives," he said.
Nicholson and Cuthers' sentences also covered drug offending they admitted.
- By Jimmy Ellingham of APNZ
