Rotorua man Shane Roberts on trial for murder of baby Karlos Stephens

Shane Claude Roberts, 61, faces one charge of murder over the 2014 death of 10-month-old Karlos Stephens. Photo / Andrew Warner

Rotorua baby Karlos Stephens was just 10 months old when he died from "significant" head trauma that caused bleeding behind his eyes and on the surface of his brain.

Now a jury is being asked to decide whether Shane Claude Roberts, 61, was the man responsible.

Roberts has pleaded not guilty to the murder, sometime between November 29 and 30, 2014. His trial began today in the High Court at Rotorua.

The Crown argues Roberts assaulted the baby - causing the fatal injuries - and was "reckless" as to whether he died or not, but Roberts' lawyer willed the jury to ask whether it was "truly a case of murder" or if Roberts was even the person responsible.

The Crown opened its case this morning before Justice Sarah Katz and a jury of six men and six women.

Karlos Stephens was just 10 months old when he died. Photo / File

Prosecutor Anna McConachy told the jury Karlos was "tragically killed" as a result of "significant trauma to his head" while in Roberts' care.

The injuries suffered could not have been caused without violence or accidentally and Roberts was "reckless" when it came to determining to whether the baby died or not, she said.

Karlos, a twin, was born on January 17, 2014 to Pamela Stephens. He and his brother were five weeks premature.

She moved in with her mother following the birth but after a few months, the pair had a falling out and parted ways.

Pamela Stephens already had four other sons and was "struggling to cope with the twins", McConachy argued.

Agencies dealing with Pamela at the time believed she was suffering from post-natal depression and it was around that time Pamela met Roberts, who she knew as Kraut.

Roberts already had two twin girls with his ex-wife and offered to help Pamela, McConachy said.

Pamela allowed Roberts to take the boys as it was the "stable care the twins needed".

By July 2014, Roberts was the primary caregiver and referred to himself as the boys' "father".

He was living at an address on Alison St and received help looking after the twins from both his ex-wife and his twin daughters, who were both 18 years old at the time.

On November 26, Robert's ex-wife and his daughters went down to Christchurch for one of the girls' graduations.

At this time, Roberts' Alison St address did not have power but his ex-wife went shopping to ensure he had everything he needed to look after the twin boys.

Roberts texted Pamela to ask if she wanted to stay at the Alison St address to spend time with the boys, as she had been living with a friend.

Pamela jumped at the opportunity as she had not seen her twin boys for "some time", McConachy said.

Shane Claude Roberts, 61, faces one charge of murder over the 2014 death of 10-month-old Karlos Stephens. Photo / Andrew Warner

On November 29, Robert's ex-wife and daughters called him on speakerphone. During the call he told them Karlos was a "bit sick", "grizzly' and could have the flu.

The daughters asked Roberts to put the baby on the phone and remembered Karlos laughing as they spoke to him, she said. They told Roberts to take Karlos to the doctor.

Roberts took the twins back to the Alison St address, where Pamela recalled Karlos wanting "to be held and cuddled" and acting "clingy", she said. He rejected food but had a drink of orange juice.

Roberts left with the boys to take Karlos to the doctor.

He did not come back to the address that night but arrived banging on the door around 7.30am the next day saying "Karlos was not breathing".

Pamela had said they needed to take him to the hospital, while Roberts said they should go inside and call an ambulance, the Crown said.

The pair drove to the hospital, with Pamela holding Karlos and "willing him to live".

She ran into the hospital holding the baby as medical teams took over to revive him. However, they were unable to do so and he was pronounced dead.

There were no physical injuries on the baby but an internal examination showed "significant head trauma" and bleeding across the surface of the brain.

He also had extensive haemorrhaging behind his eyes and ultimately died from a "lack of blood and oxygen to the brain".

A homicide investigation was launched.

McConachy said the medical evidence showed Karlos had been assaulted and these injuries caused his death.

Roberts had previously said he had the twins at a Homedale St address and as he went to feed them, he found Karlos "floppy" in his cot, she said.

Robert's lawyer Simon Lance made a brief opening statement saying "no one intended or wanted young Karlos to die" and it was clear everyone close to the baby was "distraught" by his death.

He asked the jury to question whether it was "truly a case of murder" and whether Roberts was responsible.

He said issues of both timing and evidence could prove Roberts "did not cause the injuries" that caused this "sad tragedy" and asked the jury to remember there had a been six-year time delay since the event, which could cause difficulties for some witnesses when it came to recalling the events.

He reiterated Roberts was not arrested for murder until four years after the death in 2018.

The trial continues.