UPDATED 11.08pm: Mr Pora's lawyer Jonathan Krebs has spoken to media in Auckland.

He's thanked supporters, and says attention is now turning to the next step.

"And over the next four weeks we as a team will be working on those submissions and naturally our argument will be that there should be no retrial."

Historic day as Pora's convictions quashed

The Privy Council has accepted expert evidence, which said Mr Pora suffered from a form of fetal alcohol syndrome disorder.

It says that evidence calls seriously into question whether his confessions can be regarded as reliable.

"The board decided therefore that those convictions had to be quashed and that Mr Pora's appeal had to be allowed."

The Privy Council has also ordered that submissions be taken on whether Teina Pora will face another retrial.

Police Assistant Commissioner Malcolm Burgess says they will take time to fully consider the judgement and expect to be consulted by Crown Law regarding any submissions on re-trial.

He says they note the comments from the decision that stated that none of the police officers exerted pressure on Mr Pora - if anything they were "fastidiously correct in their treatment of him."

The four week period for submissions by the Crown means this matter is still subject to judicial process, and police won't be making further comment at this time.