A killing spree on a lonely track to Nelson in 1866 made the Marlborough goldfields look like the Wild West.
James Battle was the first to be murdered, on June 12, 1866 on the Maungatapu Track in the Pelorus Valley.
The next day, four more men were killed uphill from the river where the track climbs over the Bryant Range to Nelson.
On a winter's afternoon, Felix Mathieu and his three companions were ambushed on a steep hill track by men pointing guns and knives at them.
Richard Burgess and his gang lay in wait at a trap they had prepared at a big rock beside the track about 2km from the summit. They forced their victims up a creek and on to a hillside where they were tied up and variously strangled, stabbed and shot.
The gang killed the travellers' packhorse and made for Nelson with their victims' gold and cash, where they were barbered and bathed and spent freely - and made plans to rob a bank.
The Burgess gang, clockwise from top, Joseph Sullivan, Thomas Kelly, Philip Levy, and Richard Burgess. Source: Alexander Turnbull Library
This was the case of the Maungatapu murders, by New Zealand's most notorious goldfields gang, in June 1866. The colony was gripped by the crime for weeks.
The Burgess gang, all Londoners, were New Zealand's version of Australian bush ranger Ned Kelly. All but one of the foursome had been transported to Tasmania as convicts.
Burgess, Thomas Kelly and Philip Levy were convicted and hanged in Nelson. Joseph Sullivan turned on his gang, giving evidence against them, and in return was not charged.
He was subsequently convicted of a separate murder committed one day earlier but escaped the noose because of the authorities' need to protect police informers, and the sentence was commuted to life imprisonment.
Now a Christchurch author controversially says his research indicates the Supreme Court jury got it wrong.
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"It seems clear that two innocent men were executed," says John Rosanowski, who has published his historical novel on the case, Treachery Road.
"Kelly and Levy arrived back in Nelson unaware of the murders. Kelly thought robbery had taken place. Even on the gallows, Kelly said he was being executed for the murder of people he hadn't even seen."
The four men travelling from Deep Creek to Nelson on the Maungatapu Track were ambushed at what is now called Murderers Rock and killed nearby. Map: topomap.co.nz
Mathieu was the proprietor of Cafe de Paris at the Deep Creek goldfield in Marlborough's Wakamarina Valley, where the output of gold had fallen.
Levy had visited Deep Creek and heard of Mathieu's plans to go to the West Coast to set up a new store, so would have known the businessman would be carrying a substantial amount of money.
Mathieu set out with storekeepers John Kempthorne and James Dudley, and gold miner James de Pontius. With a packhorse, they were walking over the Maungatapu Track, then a rough route between Marlborough and Nelson and now a shingle road popular with mountainbikers.
The gang, who had been staying at Canvastown, left ahead of the Mathieu party. On their way to their trap, at what is now called Murderers Rock, they caught up with solo traveller James Battle, 54, a labourer and former whaler.
Near the Pelorus River, they partially strangled Battle, robbed him of his 3 pounds 17 shillings, and left him to die in a shallow grave.
Only gradually did the Nelson police become convinced that Mathieu's group was missing, after a friend who had been following them at a distance became concerned and made his own inquiries.
Eventually a massive search got going and one by one the gang were arrested after the first, Philip Levy, was recognised in the Wakatu Hotel by a Deep Creek gold miner.
But the victims weren't found until Sullivan confessed, taking the police offer of a pardon to any informer other than the actual murderers.
Incensed, Burgess penned a 50,000-word counter confession, in which he stated he and Sullivan were the killers and sought to clear Levy and Thomas Kelly.
Other authors have pointed to the unreliability of parts of Sullivan's story, but Rosanowski says his research of British and Australian convict records found Sullivan was even more of a liar than had been thought.
He added that the Sullivan's bloodied shirt, found under a log beside the Maungatapu Track, was "proof positive" of his involvement.
"The blood-stained shirt and the fact he hid it should have destroyed his credibility as a witness."
Wayne Martin, author of Murder on the Maungatapu, a Narrative History of the Burgess Gang and their Greatest Crime, says it is more than likely Sullivan was a direct participant in all five murders - and the killing of the surveyor-engineer George Dobson on the West Coast in May 1866.
Martin has no doubt Kelly was an active participant in most of the murders but says Levy probably wasn't, being "more a bit player".
Their claims to have gone ahead while the other two were back down the track doing the murders were not credible.
"They were in fact identified on the track after Battle's murder with the other two by the Havelock Magistrate Pilliet as he rode past. Their journey to Nelson would have taken five hours or so at the most, but some 27 hours or so later they still hadn't made it, as they allege the other two came upon them on their night journey back to Nelson after committing the main murders.
"Kelly's excuse that it took so long because he ... 'drank too much water' is laughable. At trial he continually tried to get witnesses who were on the track to say that they had seen evidence of their camp etc, but no witness out of the several who were on the track over the relevant period corroborated their claim.
"Also Levy first told his Rabbi that he 'was with the others the whole time' - as a means of verifying they did not commit the murders - yet changed his story later to fit with the one cooked up by Burgess and Kelly, that Levy and Kelly had gone on ahead."
The execution was covered at length in the Herald, the story from a Nelson Examiner reporter, who was permitted to observe the hangings, occupying two-thirds of a broadsheet page.
Nelsonians perched themselves on Church Hill and other high points for a glimpse of the grim proceedings, which ran late owing to long speeches by Kelly and Levy, who proclaimed their innocence to the last.
Burgess, seemingly calm, shook hands with a host of officials, including the police Inspector Robert Shallcrass, before ascending the gallows and kissing his rope.
After the hangings, the men's necks were dissected to determine the cause of death. It was strangulation, rather than severance of the spinal cord.
Plaster casts were made from moulds of the men's skulls, allowing their study for "phrenology", now considered a pseudo-science, in which it was thought personal characteristics could be determined from the shape of the head.
The provincial superintendent, Alfred Saunders, kept the men's preserved skulls and brains and later gave them to the Nelson Phrenological Society.
The five Maungatapu victims were buried at the Wakapuaka cemetery and a memorial was erected. A plaque marks the location of Murderers Rock on Maungatapu Track.
Sullivan was despised, both in prison and in the community. He was transferred to Dunedin, then to Mt Eden jail, before being deported to England in 1874. He returned to Australia, where he was arrested. The state of Victoria tried to deport him to New Zealand, but New Zealand refused.
• This story was first published on October 10, 2017