A new investigation has been launched into disgraced Waikato health boss Nigel Murray.

Hours after the Waikato DHB released records on Friday detailing Murray's spending, Health Minister David Clark announced a fresh probe.

Clark has directed the State Services Commission to carry out an investigation into the circumstances surrounding Murray's misspending.

TOM LEE/STUFF Waikato DHB Board chairman Bob Simcock (file photo).

Murray resigned as Waikato DHB chief executive on October 5 partway through an independent inquiry which found evidence of unauthorised spending.

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The Waikato DHB accepted Murray's resignation on the basis he pays back funds owed.

In a statement, Clark said he had instructed State Services Commissioner Peter Hughes to investigate alleged wrongful spending by Murray.

"It is critical that transparency in and accountability for these processes and outcomes is maintained," Clark said.

The State Services Commission investigation will examine the circumstances of any unauthorised or unjustified spending by Murray, any similar conduct by other DHB staffers, and any decisions made by the Waikato DHB relating to Murray's spending.

To date, Murray has paid back $30,000 to the DHB but still owes taxpayers about $41,000, according to DHB documents.

In the past financial year, Murray racked up expenses totalling $91,506.

By comparison, Murray's predecessor, Craig Climo, spent $9750.60 during his final 18 months as Waikato DHB chief executive.

Murray's spending was revealed in a document dump put on the Waikato DHB's website at midday on Friday.

His financial records were filed late for each year he was employed by the DHB.

Murray was appointed chief executive in 2014 and during his three-year tenure took 16 overseas trips on the taxpayers' purse.

Seven of those trips related to the DHB's virtual health initiative, SmartHealth, or were described as IT-related trips.

DHB records show Murray spent $50,000 on relocation costs when moving from Canada to Hamilton in 2014 - $25,000 more than permitted.

During the 2016/17 financial year, Murray took five domestic flights without explanation. The flights cost taxpayers $5004.

When initially confronted with allegations of unauthorised spending, Murray casually dismissed concerns, saying the funds related to a taxi fare and a meal.

He told Stuff he welcomed any inquiry into his spending and would fully cooperate with investigators.

Waikato DHB chairman Bob Simcock was alerted to the new probe about 20 minutes before it was publicly announced.

Simcock said the new investigation was not a reflection of any shortcomings with the DHB's own probe into Murray.

"I'm confident in the processes we undertook and welcome any review of them," Simcock said.

Simcock agreed with Clark that Murray's actions did raise issues of trust in the public domain.

Simcock was first alerted to concerns about Murray's charging of expenses to the DHB on June 7 but took a further month and 12 days to inform the full board.

​Nigel Murray file

June 7: Senior staff alerted the Chair of the Board to concerns they had about Dr Murray's charging of expenses to the DHB.

June 8: Chair visited State Services Commission in Wellington to seek guidance about how to proceed.

June 12: Chair informed Director General of Health and the Office of the Minister of Health about the concerns having been raised.

June 19: Chair engaged external employment lawyer to provide independent legal advice.

June 19-30: Gathering of documents and information. Chair of Board briefed the Chair of the Audit Committee.

July 4: Chair of Board and Chair of Audit Committee met with Dr Murray to outline concerns and seek feedback. Chair of Board reported to the Remuneration Committee by teleconference. The Committee asked for further checks to be made before deciding next steps.

July 17: Board Chair and Chair of Audit Committee again met with Dr Murray to get his responses to information gathered. Remuneration committee again met by teleconference and decided that the full Board should be briefed and should recommend a formal independent investigation be undertaken.

July 19: Special Meeting of the DHB Board was held by teleconference with legal counsel in attendance. The Board delegated the Remuneration Committee to commission an independent investigation and oversee the process. Early August External legal counsel instructed specialist Barrister to carry out the independent investigation.

September 22: As part of the ongoing investigation, the Barrister conducting investigation presented Dr Murray with a draft report which included proposed findings and sought his response.

September 29: Remuneration Committee met with legal counsel in attendance, and was informed that Dr Murray had made an offer of resignation.

Legal counsel briefed the committee on the content of the investigator's draft report. The Committee recommended that the full Board accept Dr Murray's offer of resignation with immediate effect, on the basis that he agreed to repay all outstanding amounts.

October 5: A Special Meeting of the Board agreed to accept Dr Murray's offer of resignation.

Source: Waikato DHB