Dr Napthine, of Port Fairy, said he got advice from the Department of Premier and Cabinet about the requirements for the caretaker period prior to the 2014 election and “they were fully followed”.

He was commenting on a request by Labor deputy premier James Merlino for Victoria Police to investigate the leave status of ministerial staff employed by the Liberal Napthine government during the 2014 state election campaign.

Mr Merlino claims only one ministerial staff member from about 200 ministerial staff took leave during the caretaker period.

His claims come after Victoria Police reopened an investigation into Labor’s payment of ‘red shirts’ field officers, many of them electorate officers, during the 2014 campaign.

After a years-long investigation, the state ombudsman Deborah Glass earlier this year found the payment of the field officers from parliamentary funds was wrong. 

The ombudsman said 21 Labor MPs had misused more than $400,000 of parliamentary funds to pay the field officers. 

Dr Napthine said Labor’s claims against the Liberals were not “tat for tat” for the investigation that Labor was now facing.

He said Labor had been found to have done wrong by the state Ombusman while the claims against the Liberals were “spurious allegations that have no substance”.

“It’s a desperate attempt to deflect attention from the rorting of taxpayers’ funds that Labor had been found guilty of,” Dr Napthine said.

In his letter to Victorian Chief Police Commissioner Graham Ashton, Mr Merlino also said he was providing evidence of clear political campaigning by electorate office staff of 18 current and former state Coalition MPs. 

None of the MPs are from the south-west.

Mr Merlino’s letter made veiled references to the police inquiry into Labor’s misuse of funds.

He said that given the approach police had taken into recent related investigations, “the material I have provided directly indicates potentially serious offences being committed in this matter”.