A jailhouse witness' evidence "was all a lie" during the double-murder trial of David Tamihere, a court has heard.
The man, known only as "Witness C", is accused of perjury and attempting to pervert the course of justice after he testified that Tamihere told him in prison that he'd killed Swedish tourists Urban Hoglin and Heidi Paakkonen and dumped their bodies at sea.
The alleged false testimony came at Tamihere's murder trial some 27 years ago, but Witness C's name and identifying details have been suppressed since.
Tamihere was convicted of the murders and eventually released from prison in 2010 after serving 20 years, but he has always professed his innocence.
Witness C entered a plea of not guilty to eight counts of perjury and one of attempting to pervert the course of justice at the start of his trial today before a jury and Justice Christian Whata in the High Court at Auckland.
The case was laid as a private prosecution by Witness C's longtime prison inmate and serial litigator Arthur Taylor, and will be led by lawyer Murray Gibson.
Witness C was one of three jailhouse informants who gave evidence for the Crown during Tamihere's trial.
The case has not been brought forward for the re-litigation of Tamihere.
In Gibson's opening address today, he said the case would be decided on "two very significant documents" from Witness C.
"On the 25th August, 1995 [Witness C] swore an affidavit effectively confirming that he lied and gave false evidence in a High Court murder trial five years earlier," Gibson said.
However, in 1996 Witness C retracted his affidavit.
Then in June 2007, Gibson said Witness C wrote Tamihere a hand written letter stating the "trial evidence was all false and fabricated by the police anyway".
"It was all a lie," Gibson said of Witness C's evidence at the murder trial.
The letter also came with an offer from Witness C to give a complete statement to exonerate Tamihere of the murders.
Gibson said Witness C lied for personal reward and for other advantages that the police were offering him, such as assistance in his upcoming parole hearing.
During his opening address, Gibson showed the jury the original letter and affidavit.
He said in the affidavit, Witness C acknowledged he may face serious repercussions as a result of what he said in the legal document, which was made "at his own insistence and instigation".
Gibson said paragraph three of the affidavit showed Witness C accepted what he did was morally and legally wrong.
It also said a sum of up to $100,000 was available for Witness C from police if he gave helpful evidence during the murder trial.
The letter claimed the injustices were a result of police corruption.
"The police's contrived and fabricated evidence," Gibson said.
Witness C's lawyer Adam Simperingham said his client's evidence during the murder trial was true.
He said, in hindsight, "we know that some of the substance that what Witness C said was not true", referring to where the bodies were disposed.
However, Simperingham said Tamihere had told Witness C he had dumped the bodies at sea.
Hoglin's remains were later discovered by pig hunters in 1991 in the Wentworth Valley near Whangamata on the East Coast, about 70km from where the murders were alleged to have taken place. A post-mortem examination indicated that he had been stabbed.
Paakkonen's remains have never been found.
Simperingham said the authorship of the hand written letters was not in question.
But he told the jury that "the letter was not worth the paper it was written on".
At the murder trial, Witness C testified that Tamihere had told him he met the Swedes at a picnic or camping area before he sexually assaulted and killed both.
He told the court that Tamihere killed Hoglin by beating his head with a lump of wood, and dumped their bodies at sea in the Firth of Thames.
Hoglin, 23, and Paakkonen, 21, disappeared in April 1989 after leaving their car at the end of the Tararu Stream road in the Coromandel Ranges.
Taylor has said in court documents that he had never met or spoken to Tamihere.
He said that his motivation for bringing the prosecution was "to maintain the integrity and reputation of the criminal justice process and demonstrate to anyone contemplating giving false evidence that they can be held accountable".
Tamihere was living rough in the bush at the time the Swedes disappeared, having absconded after pleading guilty to having sexually violated a woman in Auckland in 1986.
Tamihere admitted stealing the Swedes' car but denied having met them.
Witness C's identity to remain hidden
The identity of Witness C will stay hidden after the Court of Appeal today dismissed a May appeal from Taylor against the court's suppression order.
Justices Stephen Kos, Christine French and Mark Cooper said Taylor was not the applicant for the suppression order, the prosecutor for the 1990 trial, or a member of the media and unable to make the appeal under the Criminal Procedure Act.
The Court of Appeal further reiterated the order by prohibiting publication of the name or identifying particulars of Witness C.
"Mr Taylor has failed to demonstrate exceptional circumstances that would justify the extraordinary step of removing permanent name suppression," the decision read.
No order for costs was sought by Witness C.
"In any event, given the essentially criminal nature of the appeal and the public interest in clarifying the law, we make no order for costs," the Court said.
Justice Christian Whata also told the High Court jury this morning that they must not name Witness C outside of court to any friends or family.
Paakkonen and Hoglin disappear on the Coromandel Peninsula
Tamihere convicted of murdering the Swedish travellers
Hoglin's remains found near Whangamata
Court of Appeal rejects Tamihere's appeal
Tamihere denied leave to appeal to Privy Council
Witness C swore affidavit retracting his evidence
Witness C retracts his retraction
Tamihere released on parole
Private prosecution alleges Witness C lied at Tamihere's trial