Ihaka Stokes murder accused says he lied to police to cover for boy's mother

Troy Kevin Taylor is on trial in the Christchurch High Court for the murder of baby Ihaka Stokes. Photo / Fairfax

The man accused of murdering Christchurch infant Ihaka Stokes says he lied to police to cover up for the boy's mother, but an expert witness has today cast doubt on his story.

Troy Kevin Taylor, 23, says his former partner, Ihaka's mother Mikala Stokes inflicted the boy's fatal injuries in a four-hour window while he was out of the house.

Taylor, who denies murdering 14-month-old Ihaka on July 3, 2015, is expected to testify next week.

He will rely on expert evidence that children with severe head injuries can, in rare cases, spend several hours in a "lucid state" before going into cardiac arrest and dying.

But on day five of his murder trial at the High Court in Christchurch, neuropathologist Professor Colin Smith questioned the validity of Taylor's story.

Ihaka Stokes was 14 months old when he died. Photo / Supplied

The UK expert believed it was a "maximum of minutes" from the time Ihaka received his injuries before he became unconscious.

Crown prosecutor Mark Zarifeh asked Smith to comment on defence suggestions that Stokes inflicted the injuries in the afternoon - at least three hours before the de facto stepfather found him unresponsive in his cot.

"In my opinion, that is not an explanation for the pathology that is present in this case," Smith said.

The evidence, Smith said, "absolutely points" to Ihaka going into cardiac arrest "very close to the point at which the injuries have been inflicted".

Yesterday, the jury watched Taylor's recorded police interview where he told detectives how he heard a "loud bang" the night Ihaka died and thought he had fallen in his cot and hit his head.

But today, defence counsel Phil Shamy said Taylor will say he did not tell police the truth because "he was covering up for the mother of the child".

Taylor says when he got home from getting a tattoo, Stokes had already put Ihaka to bed.

He says he heard Ihaka grizzling in his cot but when he popped his head into the room, he thought the child was falling asleep.

When he checked on him again, about 8.30pm, the child was floppy with raspy breathing.

Taylor thought something was wrong because Ihaka had not acknowledged him as he normally would, Shamy told the jury of six men and six women.

Ihaka did not reach up to him as he said to police earlier, and the child did not climb onto his chest.

Taylor will say he thought "something had happened" to the infant but didn't want to get 21-year-old Stokes "into trouble".

The murder accused will say he comforted Ihaka and when he thought he had gone to sleep, wondered if he had been "over worrying the situation".

He returned to bed himself "concerned" and wondering whether he should involve a doctor.

Taylor vowed to check on the boy throughout the night.

About 10.30pm, he found Ihaka lying diagonally in the cot on his stomach and thought he may have had "some sort of seizure or fit".

He saw blood around the toddler's mouth so turned on the light, and saw him pale and unresponsive.

The alarm was raised, an ambulance came and rushed him to hospital. But Ihaka died at 11.40pm.

Smith said Taylor's story "does not fit with the neuropathology in this case".

He did not believe it was a "reasonable possibility" for any lucid interval, or time elapsing between any injuries and Ihaka being found unconscious.

The Crown and the defence agree there were no intruders on that fateful night and that the boy's 59 horrific injuries, including broken bones, were not accidental.

The Crown says Taylor was suffering from sleep deprivation, headaches, and irritability caused by multiple concussions around the time Ihaka was developing an ear infection, when he allegedly caused the fatal injuries.

Stokes, who was 36 weeks' pregnant at the time of Ihaka's death with her second child, repeatedly denied the accusations when she gave evidence earlier this week.

Taylor also denies assaulting the child on July 2, 2015 - the day before the alleged murder.

The trial, before Justice Cameron Mander, will continue on Monday morning.