This raises the prospect that a 21st century jury would have to decide on a cold case from the last century, against an accused now in his early 70s who has already served 20 years in prison.
But the court has left the decision on whether or not to proceed to a new trial up to Crown prosecutors.
If they decide not to go ahead, it would mark the end of proceedings but leave many questions about the case unanswered.
Approached on the question of a retrial, the Crown Law Office said in an email that various factors would be taken into account and a decision made in due course.
The matter is next due to be heard on the “nominal” date of May 13, in the High Court at Auckland.
“But the decision about whether a retrial will proceed will not necessarily be made by that date,” Crown Law said.
Last sightings of couple
Höglin, 23, and his fiancée, Paakkonen, 21, were seen alive and together in Thames on April 7, 1989.
Some witnesses, however, believed they saw them in the northern part of the Coromandel Peninsula on April 8.
Their distinctive white Subaru four-wheel-drive station wagon with a bull bar was seen at Tararu Creek Rd, on the western side of the Coromandel Peninsula, north of Thames, on April 9.
Sven Höglin and Heidi Paakkonen.
Tamihere later admitted that he stole the car and sold or dumped the backpackers’ possessions.
But he said that he had never met the young couple, who had disappeared into the bush.
Despite this, Tamihere was charged with murdering them and found guilty in 1990, after a jury trial based partly on evidence from a fellow remand prisoner who, many years later, was discredited and prosecuted for perjury.
Tamihere was already in prison serving a life sentence when Höglin’s remains were found in the bush by pig-hunters in 1991, many kilometres away from where they should have been if the prosecution’s theories were correct.
The evidence was that Höglin died close to where his body was discovered.
Paakkonen’s remains have never been discovered, although her jacket and wallet were found near Crosbies Clearing.
Tamihere has always maintained his innocence, taking his case through an exhaustive series of court battles, twice to the Court of Appeal and finally to the Supreme Court.
He pursued the case long after he was released from prison on parole in 2010.
In 2024, the Court of Appeal found there had been a miscarriage of justice because of the evidence the discredited prison informant, Roberto Conchie Harris, gave at the original High Court trial.
Despite this, the Court of Appeal said new evidence in the case trumped that and “for that reason, the miscarriage does not justify setting the convictions aside”.
However, the Supreme Court now says that was wrong, and has overruled the Court of Appeal decision.
David Tamihere being led into court in 1989. Photo / NZME
In today’s unanimous ruling, it quashed Tamihere’s convictions.
In doing so, it said that there was a “fundamental error” at Tamihere’s trial, which made the trial unfair.
It also said that there had been a “recasting” of the Crown’s theory of what happened, which meant that Tamihere’s convictions were now based on issues, including questions of credibility and reliability, which had never been tested before a jury.
On the run from police
At the time of the Swedes’ disappearance, Tamihere had been on the run from police for unrelated matters for about three years and had been living mainly in the bush on the Coromandel Peninsula.
Tamihere admitted he took the couple’s car but said he never met Höglin and Paakkonen and knew nothing about them going missing.
The young couple’s disappearance led to a months-long search involving police, search and rescue crews, the Defence Force and Coromandel residents.
Tamihere was later charged with their murder, based largely on circumstantial evidence, including the inference that Höglin and Paakkonen were dead, as neither body had been found at that time.
The Crown case also relied on the evidence of two trampers, John Cassidy and Theodore Knauf, who identified Tamihere as the man they met at a place called Crosbies Clearing on the afternoon of Saturday, April 8, 1989.
This was near Tararu Creek Rd, where the couple’s car was sighted the following day.
Roberto Conchie Harris was found guilty of perjury after he gave evidence at Tamihere’s trial. Picture / Peter Meecham
The trampers said the man they encountered was with a young, blonde-haired woman who resembled Heidi Paakkonen.
The trampers’ evidence was supported by that of Harris, who told the trial he had talked to Tamihere while both men were in prison on remand.
He said that in those conversations, Tamihere admitted killing the Swedes.
He also said that Tamihere had told him that he was in the bush with Paakkonen and had been almost “sprung” by a young couple there – with the Crown inferring that the couple were the two trampers.
Harris also said that Tamihere had talked about giving Höglin’s watch to one of his sons, which supported other Crown evidence suggesting that the watch had been in Tamihere’s possession following Höglin’s disappearance.
Sentenced to life imprisonment
Tamihere was convicted in December 1990.
He was sentenced to life imprisonment but appealed his convictions to the Court of Appeal.
In October 1991, before the appeal could be heard, Höglin’s remains were found in the Wentworth Valley, on the peninsula’s eastern side and 70km by road from Crosbies Clearing.
A stone marks the spot where Sven Höglin’s remains were discovered by pig hunters in October 1991.
Höglin’s watch was found with his remains.
The Court of Appeal first dismissed Tamihere’s appeal in 1992, saying Tamihere had the ability to move Höglin’s body to the place where it was found.
Tamihere was denied leave to take his case to the Privy Council in London, which at that time was New Zealand’s highest appeal court, in 1994.
Harris convicted of perjury
In September 2017, Harris was convicted of perjury in relation to the evidence that he gave at the trial, including that Tamihere had talked of being in the bush with Paakkonen and had almost been “sprung” with her while there.
Following this, Tamihere was granted a rarely-used exercise of the “prerogative of mercy”, under which the Governor-General could intervene in a possible miscarriage of justice and refer a case back to the Court of Appeal.
The grounds were that the location of Höglin’s remains and Harris’s perjury conviction may have raised doubts about the trampers’ identification evidence and could indicate a miscarriage of justice had occurred.
The prerogative of mercy was granted in 2020.
In July 2024, the appeal court judges found that the admission of Harris’ evidence at trial may have affected the jury’s verdict and, therefore, a miscarriage of justice had occurred.
However, the court also said it was satisfied that Tamihere was guilty, nonetheless.
It declined to quash the convictions.
‘Fundamental error at trial’
The Supreme Court’s decision released today said that was not the correct outcome.
“There was a fundamental error at trial which made the trial unfair,” the Supreme Court decision said.
“The radical recasting of the Crown theory of the case … meant that … Mr Tamihere’s convictions were upheld on a case raising issues, including questions as to credibility and reliability, that had never been tested before a jury.”
David Tamihere says he never met the Swedish tourists. Photo / NZME
One of the issues was Harris’ perjured evidence which the court said was “concocted to secure convictions” and provided material support for the Crown’s identification evidence.
Another change in the Crown case arose in response to the discovery of Höglin’s body after the trial and the fact that evidence suggested he was killed close to where the remains were found.
“This has required a radically different Crown theory,” the Supreme Court said.
“That theory … entails focusing on events connected to the offending occurring at multiple locations across a different, significantly larger geographical area, and over many hours.
“There are now also two likely crime scenes.”
The Supreme Court said that there were now simply “too many questions” on the Crown’s new theory of the case.
“That does not mean that a jury, properly directed, could not possibly be satisfied of guilt, but that would need to be decided on a retrial, which this court has now directed.
“It will, however, be for the Crown to decide whether or not to direct a retrial.”
New evidence presented
Among the new evidence that Tamihere’s lawyers presented to the Supreme Court was an affidavit from the late businessman, politician and author Sir Bob Jones.
“Sir Robert recounts, amongst other matters, an encounter with the late Detective Inspector John Hughes, the officer in charge of the case against Mr Tamihere and the person responsible for the police inquiries leading to the charges laid against Mr Tamihere,” the court decision said.
“Sir Robert says that the encounter took place the night after Mr Tamihere was convicted of the murders.
“He describes being grabbed by a ‘very drunk’ Detective Inspector Hughes who told Sir Robert that he ‘got’ Mr Tamihere on three points and had ‘made them all up’.”
The Crown responded that the evidence was “unreliable … vague and inadmissible”.
The Supreme Court justices said they had reached the conclusion that Tamihere’s appeal should be allowed without needing to consider the affidavit.
Ric Stevens spent many years working for the former New Zealand Press Association news agency, including as a political reporter at Parliament, before holding senior positions at various daily newspapers. He joined NZME’s Open Justice team in 2022 and is based in Hawke’s Bay. His writing in the crime and justice sphere is informed by four years of frontline experience as a probation officer.