66-year-old Malcolm Rewa has been sentenced to life in prison for the 1992 murder of South Auckland woman Susan Burdett

In 1998 he was convicted of raping the 39-year-old, but denied killing her.

Private investigator Tim McKinnel fought for Pora's release - after he was wrongfully convicted of the murder.

He says it's been a bizarre process.

But McKinnel says he's concerned some parts of the case still haven't been properly confronted.

He says some lessons remain to be learned - and there should be a systemic review of what and how things went wrong.