A drunk driver who killed another motorist in a head-on collision and then hitched a ride home will not do jail time.

Xingyu Shang, 27, pleaded guilty to charges of careless driving while under the influence of alcohol causing death of 23-year-old Luke MacKenzie, and failing to stop after a crash.

He was sentenced to nine months home detention by Judge Gus Andree Wiltens at Manukau District Court this morning, where dozens of the victim's family members crammed into the public gallery.

This couple's son was left for dead by a drink-driver, but they don't want the man jailed


The judge's decision came after a rare gesture by the MacKenzie family who gave the court the green light to impose a sentence lighter than imprisonment after an emotional restorative justice conference with Shang and his relatives.

But Luke's father Martin did not want that to be confused with forgiveness.

"We have a strong sense of right and wrong and the defendant's actions are to us unbelievable, unthinkable and incomprehensible," he said in a victim-impact statement.

"The thought of someone running from the scene, leaving Luke there to die on his own... showed a level of callousness and injustice."

Outside court, Mr MacKenzie explained it would have been destructive for his relationship with his wife Tania and their two sons if they became overwhelmed by a grudge.

Martin and Tania MacKenzie being consoled by friends. Photo / Brett Phibbs
Martin and Tania MacKenzie being consoled by friends. Photo / Brett Phibbs

"We would like Mr Shang to suffer as much as we do, but he never will," he said.

"One thing I want you to remember was, Luke was young," he told Judge Andree Wiltens.

On February 24, 2014, the 23-year-old was covering an early morning shift at Air New Zealand where he had been recently promoted to a managerial role.

But minutes after leaving home, Shang - on the way home from a night on the town with friends - drove straight into him on Chapel Rd, Flat Bush.

Both cars were extensively damaged but Shang managed to extricate himself from the wreckage and flag down a motorist who dropped him at home.

Police tracked him down and he was eventually taken to Middlemore Hospital for treatment for his injuries.

While there, a blood test proved he would have been over the drink-drive limit at the time of the collision.

Judge Andree Wiltens said the two-year wait for the matter to be resolved would have weighed heavily on both sides.

But he believed the drunk driver had made a huge effort to address his offending, which included significant payments to the MacKenzie family and Luke's partner Ashley Sheppard.

"Mr Shang has done everything he could possibly have done to address his wrongdoing and make good," he said.

Luke's friend Jason Adriaase described the victim as "funny, driven, caring and with a passion for life".

He said Luke was the "glue" that held their group of friends together and lived by a simple motto: "hard work beats talent when talent refuses to work".

Shang will serve his home detention sentence in Papakura and will then be deported to China.