UPDATED 8:10am: Day one of Teina Pora's Privy Council hearing has wrapped up.

His defence team took most of the first day to outline its arguments.

They included that Pora has foetal alcohol spectrum disorder and had the mental capacity of a nine or 10-year-old when he confessed to the 1992 rape and murder of Susan Burdett.

Solicitor-General Michael Heron QC spoke for around 80 minutes today.

He suggested Pora had information about the case when he confessed in 1993, that had not been in the public arena.

He'll continue tomorrow.

DEFENCE

Lawyer Jonathan Krebs told the court Pora was born with foetal alcohol spectrum disorder.

He says at the time he confessed to the crimes, he would have had the mental age of a nine or 10-year-old when it comes to understanding.

Jonathan Krebs says information on the disability from three specialists could have led to a different outcome at Pora's original trial.

"The jury did not have the benefit, when considering the reliability of the confessional material, of hearing from the three specialists."

Mr Krebs says experts should have been allowed to give evidence at his original trial on the impacts of his disorder.

"Had they done so, they would have understood why it is that a person might make a voluntary false confession."

Susan Burdett's attempts to fight the man who raped her, may have caused them to kill her, lawyers for Teina Pora told the Privy Council.

It's believed Ms Burdett was killed with a baseball bat she kept near her bed.

Ingrid Squire, a member of Pora's defence team, has told the court in London that convicted serial rapist Malcolm Rewa carried out the crimes.

While Rewa did not kill any of his other known victims, Ms Squire argued this case was different.

"A more logical explanation is that Ms Burdett fought back. There was a weapon at arm's length and Mr Rewa needed to, as we know he did, implore as much violence as necessary to subdue her."

CROWN

The Crown claims Teina Pora had inside information on the 1992 rape and murder.

Michael Heron QC argued he didn't just make a false confession in 1993 to claim a reward which was on offer during the investigation.

Mr Heron says Pora told police he had not followed the case in the media, but had significant knowledge, especially of some details which hadn't been made public.

"It's very difficult to imagine that he could have been given the information and remember it and recount it to the police a year later."

Pora's defence team told the Privy Council his mental disability meant he didn't understand the gravity of his confession to police, and he was only trying to claim a reward which was on offer.

However, Michael Heron QC says that doesn't marry up with the fact he offered up details which were not in the public arena.

He also told the London court that Pora also spoke about the case at length with others.

"There were certainly confessionary statements both before and after the police interviews to a range of people, including the uncle and aunt."

Day 2 Preview

Blood spatter evidence is expected to be the focus, when the Crown lays out its case against Teina Pora tonight.

TVNZ Europe Correspondent Jessica Mutch told Newstalk ZB's Larry Williams the defence has had its say on the first day, and the Crown have its turn tonight.

She says there was blood splatter on Pora's league shirt, which he says comes from a rugby injury.