Convicted double murderer David Tamihere has asked a court to grant him access to aerial television footage as part of his appeal.
Tamihere, who was released on parole in 2010 and has always maintained his innocence, was granted a Royal Prerogative of Mercy earlier this year to have his case reviewed by the Court of Appeal
He was convicted in 1990 of the murders of Swedish tourists Urban Hӧglin and Heidi Paakkonen, who disappeared in Coromandel in 1989.
In 2012, Tamihere and a Television New Zealand crew flew over the crime scene and the search area, a breach of parole conditions although Tamihere wasn't recalled to prison.
He says the footage is in the public interest and will help the court appreciate the topography while the Crown says it is not immediately apparent that the footage is relevant.
Television New Zealand says the footage is available, subject to a court order.
In a Court of Appeal decision, Justice Kos said:
"[The] footage is likely to be held by TVNZ and it is at least broadly relevant to one of the grounds of the reference (being the potential inconsistency between the discovery of Mr Hӧglin's remains in the Wentworth Valley and the identification evidence placing Mr Tamihere in Crosbies Clearing)."
A hearing date to consider the application to access the footage has not been set.
Tamihere applied last year for a Royal Prerogative of Mercy, a rare legal avenue for criminal cases to be reopened where a person may have been wrongly convicted or sentenced.
The fate of the Swedish couple remains one of the country's enduring mysteries.
Three years ago, key witness Robert Conchie Harris- a jailhouse informant known as 'Witness C' - was jailed for lying in Tamihere's 1990 trial.
The private prosecution was brought by jailhouse lawyer Arthur Taylor, who has since been released on parole.
Harris told the jury Tamihere made confessions to him in prison, including that he sexually assaulted the Swedish tourists and dumping their bodies at sea.
Hӧglin's body was found in a shallow grave in the Coromandel after the trial.
Paakkonen's body has never been found.
Harris later changed his story, swearing an affidavit claiming the police offered him $100,000 for evidence against Tamihere.
His story changed again a year later - in 1996 - when he retracted the entire affidavit and claimed he had been threatened by gang members in prison.
The Police Complaints Authority investigated the allegations of police corruption and bribery and cleared the police, finding Harris' allegations of bribery had no basis.
Harris apologised for damaging the integrity and credibility of the police and reiterated that the evidence he had given at Tamihere's trial was true.
He remains in prison after being recalled twice; the first following complaints of assault and demanding money and the second after a complaint he indecently assaulted a 14-year-old girl.