- A jailhouse informant convicted of committing perjury in a controversial double-murder case was prosecuted by a pensioner and a prisoner.
- The Crown has never charged a jailhouse informant for perjury.
- The police have no special protocols for dealing with them and have no idea how many have given evidence as they don't keep records about their use.
- Prison witnesses have featured in a high proportion of miscarriage of justice cases in Canada and the United States, prompting safeguards to be ramped up in those countries. There has been no review in New Zealand of judicial safeguards.
- They have been involved in the miscarriages of justice cases of Teina Pora and Arthur Allan Thomas and their evidence has helped gain murder convictions against David Tamihere, Scott Watson and Mark Lundy.
- Several experts are calling for a review of the use of prison witnesses.
The unmasking of a prison witness who lied at a double murder trial has prompted calls for safeguards to be improved, reports Phil Taylor in the second of his two-part report.
The conviction for perjury in October of lifetime criminal Roberto Conchie Harris is a nightmare outcome for the use of prison witnesses in the criminal justice system.
This is not only because these witnesses have been involved in two miscarriages of justice and helped gain convictions in several of the country's most contentious murder cases. Name suppression, while important in encouraging the cooperation of truthful jailhouse witnesses and to protect them from retribution inside prison, may have emboldened Harris and other self-interested liars.
Suppression of his name for 27 years has served to limit scrutiny not just of Harris but the robustness of safeguards around the use of prison witnesses.
That he was prosecuted by a pensioner and a prisoner rather than by the police should be cause for concern as it invites questions about whether the authorities suffer from a blind spot or bias.
Prison witnesses in miscarriage of justice cases
A prison witness gave crucial evidence in the retrial of Teina Pora. Pora has received a government apology and $3.5 million compensation for having wrongly spent 20 years in jail for murder.
Two prison witnesses were produced at the Royal Commission of Inquiry into the murder convictions of Arthur Allan Thomas. Thomas was granted a Royal Pardon and compensation of $950,000 in 1979.
All three of these jailhouse informants claimed that the accused men confessed.
Prison witnesses have given evidence in other contentious convictions including of Scott Watson, Mark Lundy and Stephen Hudson (2009).
In the examples of Watson and Hudson there were no bodies and no murder weapon.
Secret Witness A, against Watson, recanted his testimony, saying he had lied, then retracted that claim after being interviewed by police again, and then again claimed he'd lied at trial.
In Hudson's case, no jailhouse witnesses came forward until after a reward of $50,000 was offered and information about the case distributed. Then, seven prisoners claimed that Hudson had confessed.
Arthur Allan Thomas
The Thomas commission heard from two jailhouse informants in private because "it seemed to us that the evidence was on the face of it highly improbable, and unfair to Mr Thomas unless the credibility of the witnesses was first established".
The commissioners described one as "mentally ill" and the other as "shrewd, cunning, devious and manipulative, and a man who would go to considerable lengths to shorten his sentence".
"We are satisfied that the 'prison confessions' never took place, and that evidence of the two prisoners was a tissue of lies. It causes us grave concern that very senior police officers were so ready to place credence on such unreliable, self-interested, and in the case of the first inmate, deluded evidence."
The evidence of a prison witness at Pora's retrial was found not to be credible by an independent reviewer commissioned by the National Government after the Privy Council quashed Pora's convictions in 2015.
Pora was twice convicted of the 1992 rape and murder of Susan Burdett.
In finding Pora innocent on the balance of probabilities, retired High Court judge Rodney Hansen said there was "good reason to doubt both the integrity and reliability" of the prison witness who had serious convictions for violence and dishonesty.
Police spoke to that witness in 1994 but did not call him to give evidence until Pora's retrial in 2000 by which time DNA had linked serial rapist Malcolm Rewa to semen from Susan Burdett's body. That put the onus on the Crown to try to show that Pora and Rewa knew each other in order to argue that they had acted together.
In his report, Hansen said the possibility that Rewa had acted alone seemed to have been ruled out.
At the retrial, the prison witness claimed to have seen Rewa and Pora together. He had not, however, mentioned Rewa as an associate of Pora's before Rewa was arrested.
Hansen found the process by which the prison witness identified a photo of Rewa to be suspect and noted that a senior officer on the case had given him "a personal loan of $150 and a supportive letter to the court when he was sentenced on domestic violence offending".
Tim McKinnel, a former police detective who worked for several years to expose the miscarriage of justice, finds the police's reliance on prison witnesses to be "troubling". "It is difficult to see why the police couldn't see that for themselves. There were plenty of red flags. The favourable treatment he got from police, including a senior officer on the Burdett inquiry lending him his own money, raises some pretty important questions.
"It is difficult to know what weight the jury put on his evidence, but he gave critical evidence in Pora's retrial - evidence that didn't exist at the first trial."
The prison witness has since died in a road accident.
Do the police have a conflict of interest?
Prisoners are well placed to hear confessions from other inmates. They may also be motivated to lie.
Canterbury University sociology professor Greg Newbold has practical experience to go with academic interest, having served time in prison as a young man for drug offending.
He knew several informants during that time, including the two put before the Thomas Commission. "Both got days out of jail," Newbold said. "One was hoping for early parole. He wasn't a pathological liar, he was just mercenary."
The police told the Herald that they will investigate any reported perjury offence, irrespective of whether the witness appeared for the defence or prosecution.
"Police have an interest in encouraging witnesses to come forward and be prepared to give evidence in Court, as long as this evidence is the truth," National crime manager Detective Superintendent Tim Anderson told the Herald.
The police have no data about their use of prison witnesses because they do not collect it, but Anderson was not aware of the police ever having charged such a witness for perjury.
However, while Harris' sentencing judge did not find any cases of the police having charged a Crown prison witness, Justice Whata did cite four examples where the police had charged witnesses for "perjury to procure acquittal".
Strong influences work against the police charging a prosecution prison witness for perjury, said Newbold. "They will never do it because they don't want to discourage their witnesses from coming forward and helping them. They don't want to be seen to be stamping on the toes of people they are hoping will assist them.
"I think sometimes they suspect themselves their evidence isn't very good. Look at Pora."
The prison witnesses can, however, have a disproportionate impact. Juries are ill-equipped to deal with them, unfamiliar with their calculated deviousness and inclined to think they were special because of the extra security and pageantry that accompanied their appearance in court, the late Greg King, a leading barrister of his generation, told North & South's Mike White in 2011.
"They all say the same thing, 'I was so shocked and I felt so sorry for the family and I know I have done horrible things in my life but that was just terrible what he did and that poor family without a body'. And jury members have this romantic notion of honour among thieves and how they are putting their lives at risk and coming forward against the criminal code. But it is an attribution of morality to these witnesses that anyone who's ever dealt with them knows damn well is just not the truth."
Do jailhouse witnesses receive benefits?
The police operate a network of paid informants who have received in recent years an annual total of between a third to half-a-million dollars.
This network may include prisoners who become witnesses but police cannot confirm that because they do not collect data specifically about prison witnesses.
It is generally claimed they give evidence out of a sense of civic duty unsullied by personal benefit but there are examples of the police going out of their way to put a good word in to the court or parole board.
For example, the late John Hughes, the detective inspector who headed the case against David Tamihere, flew to Christchurch to attend Harris' next parole hearing. Harris was not released on that occasion but was paroled within a year and again in 2008. He was recalled to serve his life sentence for double-murder each time following serious offending.
In a 1992 interview with this reporter, Hughes said he had attended parole hearings out of "a moral obligation to help them by pointing out that they had testified".
Prison witnesses were not offered rewards and police did not make recommendations for leniency, said Hughes, an old-style detective with a reputation for getting his man.
Witnesses A B and C had testified, Hughes claimed, because they were "sick of hearing Tamihere boasting about what he had done to the tourists".
Witness A, who also testified for the Crown in another murder case, received a third off a 12-year jail sentence for drug trafficking. The sentencing judge noted that he had put himself in "grave danger" and provided assistance of "exceptional value" without the prospect of personal benefit.
However, that assessment was contradicted by Witness A's wife in an interview with this reporter two years after Tamihere was convicted. She claimed that her husband had been short-changed because he had understood that he would be soon released and relocated overseas with his family.
In the case on which Scott Watson was convicted for the murders of Olivia Hope and Ben Smart, Secret Witness B received a phone and car from police, and also got a light sentence for charges he was facing.
What safeguards are there around jailhouse witness testimony?
There are no specific safeguards.
The police don't have any special protocol for dealing with them. As for any witness, police seek to corroborate their evidence, look at how it fits with other evidence and consider possible motives when assessing reliability, Anderson said.
In court, a warning that evidence might be unreliable is usually given by the judge to the jury under Section 122 of the Evidence Act. This applies to any witness the judge has concerns about. Otherwise, it is up to defence lawyers to warn that prison witnesses may have a range of reasons to lie.
"To be honest, the courts say, 'We'll leave it to the jury to sort out', with that Section 122 warning," said criminal procedure specialist Scott Optican.
As an alternative to relying on the claims of prisoners, officers wired for sound can pose as cellmates, a scenario used to gain a confession from Shivneel Kumar to having murdered Shalvin Prasad in 2013.
Optican, an Auckland University associate law professor, suggested that is more reliable because the confession is heard and recorded by a police officer.
"Jailhouse informants tend to come to the cops, rather than the cops initiating and reliability concerns are much more significant when that happens."
Canada and the United States have strengthened safeguards following miscarriages of justice involving prison witnesses.
Steps include pre-trial hearings, requirements that prosecutors track and disclose an informant's criminal history, past testimony and benefits received, that strong cautions must be given by judges to juries and that the number of jailhouse informants called in any one case be restricted to one.
Prison witnesses played a part in 46 per cent of 111 death row cases where the people were eventually proven innocent between 1973 and 2004, according to a study by the Centre on Wrongful Convictions at the law school of America's Northwestern University.
That made prison witnesses the leading cause of wrongful convictions in US capital cases ahead of eyewitness misidentification, false confessions and false or misleading scientific evidence.
Reviews in Canada were prompted by two high-profile cases.
Presiding over an inquiry after DNA cleared Guy Morin of the murder of a girl aged 9, Justice Fred Kaufman found that two jailhouse witnesses who claimed Morin confessed were "totally unreliable witnesses" and should not have been called.
Justice Kaufman said the allegations of prison witnesses are "easy to allege and difficult, if not impossible, to disprove". He recommended a series of stringent guidelines that preserved but limited the discretion to call such witnesses.
In the case of Thomas Sophonow, eventually cleared of the murder of a donut shop worker, 11 jailhouse informants volunteered their services.
They were narrowed down to three on the basis of their '"credibility and reliability". The former Supreme Court judge, Peter Cory, who conducted the subsequent inquiry, found that one of those three had offered to testify in the hope that charges pending against him would be dropped so he could avoid deportation. This information was not disclosed by the Crown.
The second witness was an established informant who was told that if he did not cooperate, his status as an informant would emerge in court. Again, this information was not disclosed.
The third informant, said Cory, had "heard more confessions than many dedicated priests". That witness had testified as a jailhouse informant nine times with some coming after he was convicted of perjury.
Justice Cory described prison witnesses as "a malignant infection that renders a fair trial impossible … They must be recognised as a very great danger to our trial system."
He recommended that their evidence not be put to jurors except for rare instances such as in kidnapping cases where they have learned of the whereabouts of the victim and the location has been confirmed by the police.
Bruce MacFarlane, QC, a Canadian crown prosecutor, legal scholar, and former justice official, described the jailhouse informant as the most dangerous witness of all because of a propensity to lie to curry favour with authorities they perceived to have control over their destiny, and a corresponding eagerness among law enforcement officials to use them.
The lure was strong, MacFarlane wrote in his study Convicting the Innocent, published in the Manitoba Law Journal, because they saved time and effort and could provide the "big picture" to the court.
"A jailhouse informant brings all these factors together, and adds a confession - the most powerful piece of evidence that a prosecutor can use."
"Now is the time to improve safeguards"
Back home, the issue hasn't been looked at.
There has never been a specific review of safeguards around the use of jailhouse witnesses in New Zealand. The Law Commission, whose role it is to review and reform the law, is currently reviewing the Evidence Act but does not plan to focus on prison witnesses.
A decade ago former High Court judge Sir Thomas Thorp cited prison witnesses as a common cause of miscarriages of justice when he recommended that New Zealand set up a specialist and fully independent authority to investigate claims of wrongful convictions, an authority the Government has committed to put in place.
Newbold suggests an immediate remedy would be for the judges to be required to give "a very strong caution to the jury".
McKinnel wants safeguards set out in law.
The former detective said the police tended to the view that evidence should be put forward unless it is clearly wrong or false.
"There needs to be a more precautionary approach. And, rather than a rule of thumb, it needs to be prescribed in law that their evidence can only be used if corroborated."
This was particularly important because, he said, in Pora's case the interest of police and the Crown appeared to be in defending the conviction rather than considering whether it was wrong.
Dr Bill Hodge, author of the textbook Criminal Procedure in New Zealand, said Arthur Taylor and Mike Kalaugher had "proven that the time has come that we need to look at it".
Taylor is a prison inmate who has become an accomplished litigant, and Kalaugher, a retired chartered accountant, campaigns on justice issues.
Hodge said: "I think New Zealand could learn from this case and from overseas and do better. With the Law Commission looking at the Evidence Act, now is the time to do it."
6 facts about prison witnesses
• A jailhouse informant convicted of committing perjury in a controversial double-murder case was prosecuted by a pensioner and a prisoner.
• The Crown has never charged a jailhouse informant for perjury.
• The police have no special protocols for dealing with them and have no idea how many have given evidence as they don't keep records about their use.
• Prison witnesses have featured in a high proportion of miscarriage of justice cases in Canada and the United States, prompting safeguards to be ramped up in those countries. There has been no review in New Zealand of judicial safeguards.
• They have been involved in the miscarriage of justice cases of Teina Pora and Arthur Allan Thomas and their evidence has helped gain murder convictions against David Tamihere, Scott Watson and Mark Lundy.
• Several experts are calling for a review of the use of prison witnesses.