Defence lawyer Nathan Gorham spent the past two days reviewing medical evidence that focused on two-year-old Kennedy Corrigan's fatal brain injuries 17 years ago.
Dr. Robert Macaulay testified by video call Wednesday afternoon and all day Thursday at the manslaughter trial of James Turpin.
Turpin is on trial for the second time in the death of the toddler, who was injured at her home in Central Blissville, south of Fredericton, in 2004. He was found guilty of murder at his first trial but successfully appealed.
Turpin has always maintained Kennedy was injured when she fell and hit her head in the bathtub.
Macaulay, a neuropathologist in Florida who performed a brain autopsy after the toddler died, believes she suffered some kind of trauma to the head.
Had to be severe trauma, doctor says
During the autopsy, Macaulay said, he noticed significant swelling on the left side of the child's brain.
He also observed dead brain tissue related to a deprivation of blood flow and oxygen.
On Wednesday, he compared Kennedy's injuries to those someone would suffer from violent shaking, a motor-vehicle accident or being struck with considerable force.
"The trauma that we usually talk about has to be severe enough the injury travels through the skull and to the brain and brain stem," Macaulay has said of what happened to the child. "It has to be significant."
Gorham cross-examined Macaulay about Kennedy's brain damage, the doctor's field of practice, and whether he reviewed his notes from Kennedy's autopsy and Turpin's previous trial.
Macaulay provided long, elaborate and scientific answers to the questions put to him.
"Why don't you just answer the question? Gorham asked at one point.
There were times when the defence and the Crown witness talked over each other. Once, Judge Terrence Morrison had to interrupt Macaulay to tell him he wasn't supposed to be the one asking the questions.
When Gorham asked Macculay if he was getting his information from textbooks or articles, the doctor said no, provoking Gorham to ask if he was making things up.
He also asked whether Macaulay was aware he was testifying at a manslaughter trial, to which the doctor responded "no."
Accused present by phone
Gorham said he plans to call two witnesses next week who disagree with Macaulay's medical opinion.
Turpin, who is not in custody, has been listening to the trial by phone this week because he hasn't been feeling well.
Turpin wasn't charged in Kennedy's death until 2015, when he was living in Charlo. In 2016, Turpin was found guilty of second-degree murder but three years later, he successfully appealed his conviction.
The Court of Appeal found there wasn't enough evidence of murder but ordered a new trial on the lesser charge of manslaughter.