The former head of Victoria's corruption watchdog has accused a Labor-dominated parliamentary committee of seeking to undermine its credibility for political gain.
In December, Independent Broad-based Anti-corruption Commission (IBAC) boss Robert Redlich wrote to parliament's speaker and president over concerns partisan politics had permeated the Integrity and Oversight Committee (IOC).
IBAC first became concerned when Canberra-based auditor Callida Consulting tipped off the body it had been directed by an audit subcommittee to "find dirt on IBAC and data that is not readily publicly available", Mr Redlich said.
"IBAC was advised that the IOC is looking for evidence to support a narrative that 'IBAC is not performing'," reads the seven-page letter published in full by the Herald Sun.
Callida was hired in 2021 to conduct an independent performance audit of IBAC and other integrity agencies, as required by law.
When the committee published its final report in October, IOC member and former Labor MP Dustin Halse was accused of requesting Callida remove any references to the Andrews government underfunding IBAC.
"The chair and majority of the IOC audit subcommittee seemed intent on casting IBAC in a negative light for what we can only assume were political reasons relating to the work undertaken by IBAC," Mr Redlich wrote.
The watchdog last year completed multiple inquiries linked to the Victorian Labor government, including a factional branch-stacking scandal.
Premier Daniel Andrews rejected the allegations that his government directed Callida to dig up dirt on the watchdog.
"I reject that completely. That's simply wrong," he told reporters on Thursday.
Mr Andrews said he had not seen the letter but his office could have been made aware of it.
In the letter, Mr Redlich complained about the committee's lack of fairness and leaking to the media.
The IOC is made up of four Labor MPs, one Liberal, one National and one Green. Mr Redlich said the government should not have a majority on the committee and instead be made up of a broad range of MPs.
Mr Andrews said the composition of the committee would not be changed because it had already been confirmed after November's state election.
"I'm not having a debate with a bloke who used to run an agency, who's apparently written a letter that I haven't seen," he said.
Labor MP Harriet Shing, who was IOC chair before her elevation to cabinet last year, also said she had not seen Mr Redlich's letter and insisted she was not advised by Labor members to hinder the watchdog's operations.
Opposition Leader John Pesutto said the allegations showed the government tried to damage IBAC's credibility and could amount to criminal corruption.
"This government under Daniel Andrews is concerned only with itself, looking after its mates and protecting its reputation," he said.
An opposition bid to suspend normal business in parliament on Thursday to discuss why the letter wasn't shared with MPs was shut down by the speaker and president.
The Greens backed the move, declaring the non-receipt of the correspondence must be addressed.
"You couldn't explain this with a straight face," Greens MP Tim Read said.
Outside parliament, shadow attorney-general Michael O'Brien called for a parliamentary or judicial inquiry into the allegations.
"We need to get answers from the former commissioner," he said.
Mr Redlich's five-year term in the role finished at the end of 2022, with the government appointing an interim commissioner.
