A leading lawyer says manslaughter charges could be laid over the Pike River mine explosion now that police are getting ready to reopen the investigation.
The lawyer for some Pike families, Nigel Hampton QC, says it is still possible for mine boss Peter Whittall to be charged.
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Dean Dunbar is still fighting for justice for the men of Pike River seven years on. His son Joseph Dunbar was killed inside the mine.
"You don't wipe out 29 innocent people and walk away from that," he says.
He hopes the justice he wants is closer than ever before, with mine re-entry likely - which has triggered police getting ready to reopen a criminal investigation.
Mr Hampton believes if new evidence is found inside the mine on re-entry, manslaughter charges could be possible.
"If that actual cause can be linked to some of what I believe was grossly negligent conduct on behalf of the mine and mine management, then the potential for taking a manslaughter prosecution opens up."
His opinion on the potential for charges is backed by criminal law specialist Chris Gallavin.
"A number of criminal charges could be laid - right from nuisance, which carries just a year imprisonment, through to gross negligence manslaughter, which carries a maximum penalty of life imprisonment."
Mr Hampton has 53 years of experience in the courtroom, and is an internationally respected criminal lawyer. Asked by Newshub who could potentially be charged, he responded: "Mr Whittall, he was the then general manager or CEO of the company."
Only two men, Russell Smith and Daniel Rockhouse, escaped from the tunnel seven years ago.
Now re-entry to find out what really happened could be a reality by the end of 2018.
The substation is considered a potential treasure trove of forensic evidence that could show what actually caused the mine - which had dangerously high levels of methane - to explode.
"They were playing Russian roulette with everyone who went underground," says Mr Dunbar.
Whittall now works in management at a rest home in Australia. He did not return Newshub's calls.
He's already been prosecuted under health and safety law, but those charges were dismissed after a payout.
Mr Hampton's opinion is that if fresh evidence is found in the mine's access tunnel, there's nothing to stop Whittall from facing criminal charges.