A young father of four who was found guilty of murdering his 10-month-old nephew was ordered today to serve a sentence of life imprisonment after a judge noted his continued lack of remorse for having violently injured the child.

Boston Liam Wilson was a week shy of his 22nd birthday in December 2021 when he killed Chance Aipolani-Nielson in their Birkdale, North Shore home.

His lawyers argued today that their client’s youth would make a life sentence manifestly unjust.

Justice Christine Gordon acknowledged that prior courts have found youth to be a mitigating factor for defendants under age 25, due to the poorer impulse control and emotional regulation thought to be associated with a still-developing brain. But when weighing his age against other circumstances of the case, including the disturbingly violent nature of his nephew’s death and his continuing refusal to accept responsibility, a life sentence was still appropriate, she decided.

She also ordered a minimum term of imprisonment of 15 years before he will be eligible to apply for parole.

“Chance’s head injuries indicated brain damage - among the most serious that ... a pediatric radiologist had ever seen,” Justice Gordon noted. “There were significant aspects of your evidence ... that the jury, by its verdict, did not believe.”

Wilson was found guilty in July following a two-and-a-half-week trial in the High Court at Auckland.

His own children were at a relative’s house and he had been left alone with baby Chance for only about 30 minutes when he called his partner to say the infant wasn’t breathing. When paramedics arrived a short time later, he denied having done anything to the child that could have caused injuries, witnesses said during his trial.

He repeated the denials in a series of interviews with police, although his story changed through the interviews and again at trial, the judge noted today.

Boston Wilson appears in the Auckland High Court charged with the murder of 10-month-old Chance Aipolani-Nielson (inset) in Birkdale in 2021. Photo / Jason Oxenham

“You said you’d done nothing that might have caused his injury,” the judge said of the first police interview. “You said ... you never lose control.”

During the third police interview, Wilson said he accidentally dropped the child, causing him to hit his head on the bedside table.

“Facing overwhelming medical evidence ... you finally admitted shaking Chance and the shaking caused his death,” Justice Gordon said, noting that was an admission of manslaughter but still not the whole truth as he claimed the shaking was only an effort to revive the child.

“You were very experienced with children and had completed a first aid course on babies,” the judge said. “You must have known that shaking a baby was an extremely dangerous thing to do.”

At another point, Wilson said Chance’s skull fracture might have been the result of accidentally hitting the child’s head on the bedroom door frame as he called his partner in a state of panic while holding the child.

The jury clearly found his explanations to be “extremely inconsistent with the expert medical evidence”, the judge said today, adding that her own view of what happened involved the child beginning to cry after a nap and interrupting Wilson’s videogame.

“Either in anger, frustration, stress or a combination of those, you shook Chance violently with extreme force,” the judge said. “You shook Chance repeatedly with the kind of force experienced in a serious car crash.”

As for the skull fractures, all of the medical experts said that none of Wilson’s explanations were reasonably possible. While it is impossible to know exactly how the skull fracture occurred without Wilson accepting responsibility, the judge said it was most likely the result of Wilson throwing the baby to the ground.

Defence lawyer Lorraine Smith noted today that her client’s case is unusual in several regards, including his lack of any prior criminal convictions and testimony that he had been a doting father to his own four children.

“Not one Crown or defence witness had anything negative to say about Mr Wilson,” she told the judge. “That, in a murder trial, is rare and significant.”

She said her client suffered a background of deprivation starting with the separation of his parents when he was young. His father disappeared from the picture, and as his mother worked hard to support the family Wilson began spending time at the local Black Power gang pad - using alcohol and cannabis by age 12.

But Crown prosecutor Alysha McClintock noted that at the time of the killing Wilson had been “part of a loving and supportive family” so his background shouldn’t be seen as a strong mitigating factor. His background doesn’t show the sort of deprivation “the courts see sadly all too often”, the judge agreed.

The judge also found that Wilson was eligible for a minimum term of imprisonment of at least 17 years because the vulnerability of the victim made it among the most serious types of murder. But she agreed that Wilson’s youth, when applied to that section of the sentencing law, would make a 17-year minimum period manifestly unjust.

Family members packed the courtroom this morning as the sentence was handed down. Half-a-dozen of them filed victim impact statements with the court but none elected not to have them read out loud.

The judge noted that Chance’s mother, Azure Aipolani-Nielson, said she is especially tormented due to her career in early childhood education - seeing thriving children every day, what her own son deserved.

Her family has been torn apart, perhaps irrevocably, she said.

One of Chance’s uncles agreed, adding that Wilson should be ashamed not just for what he did but for putting the family through continued agony by not accepting responsibility. Had he admitted the truth early on instead of subjecting the family to a trial, the family divide might have healed before it got so deep, the uncle said.

Wilson’s partner - Chance’s aunt - blew him a kiss through the dock window as he was escorted out of the courtroom to begin serving his sentence. She then put her head in her lap and began to cry.

Craig Kapitan is an Auckland-based journalist covering courts and justice. He joined the Herald in 2021 and has reported on courts since 2002 in three newsrooms in the US and New Zealand.