In July 2013, police said they would not press charges over the 2010 mine explosion on the West Coast because there was not enough evidence to support manslaughter charges over the deaths of the 29 underground men.
Evidence could not directly link anyone to the cause of the explosion.
The case was reopened in 2018 when the return of the 'drift' or stone tunnel leading to the mine began under the direction of the Pike River Recovery Agency.
Police later followed by sinking a series of boreholes and then lowering cameras into the mine workings, access to which is blocked by a huge rockfall at the end of the drift.
In an update to families this week, Detective Inspector Grant Wormald said the police team had worked with more than 100 witnesses to prepare detailed statements for each of them.
This included details from previous statements and information gathered during the investigation of Pike River Coal Company documents. This led to many new questions and the need for clarification.
“Last week four staff traveled to Australia to meet 45 of these witnesses. They were all engaged and supportive of the efforts being made,” Det Insp Wormald said.
“Other staff have been on the west coast this week and over the next two weeks we will complete the final 30 witnesses in other parts of New Zealand.”
Over the past five months, the research team has completed the interpretation of all subsurface photographs taken through the boreholes and worked with experts.
A significant amount of work still needed to be done to prepare the file for it to go to the Crown Solicitor.
“I am confident that we are making very good progress in determining what happened and whether anyone can be held accountable. Please remain patient in the knowledge that good progress is being made.”
In his last public interview, former Pike River mine manager and later CEO Peter Whittall – an Australian – lived in a $1.3 million block in Wollongong, south of Sydney, where he ran a retirement home. He was still there last Christmas.
Former CEO Gordon Ward, who left the company just six weeks before the explosion, was last known to be running an IGA supermarket on Australia's Gold Coast as recently as 2022. He consistently refused to provide evidence to the Royal Commission of Inquiry.
John Dow, the chairman of Pike River Coal, cooperated and was recently seen back on the West Coast.
The committee found that the board's focus on achieving production targets had set the tone for executive managers and their subordinates: 'Mr Dow's general attitude was that matters were under control unless told otherwise. This was not in accordance with good governance responsibilities.
“Combined with the approach of executive managers, this attitude exposed Pike River employees to health and safety risks.”
Operations manager Doug White also assisted in the investigation. His last known job was in mining in Australia.
Pike's statutory mine manager Steve Ellis last worked in the mining industry in Canada.
Last winter, the total police cost of the Pike River investigation since 2018 was $19.972 million.
Eleven full-time equivalent police officers were deployed for this position.
When the Pike River Recovery Agency handed over the keys to the mine site to the Department of Conservation, it had spent $71 million on the “restoration” effort, which involved looking inside the drift.
That's why the effort has cost $91 million to date.