Under the overhaul, the much-criticised Independent Broad-based Anti-corruption Commission is set to gain new powers to investigate misconduct in public office, including by MPs. That means it will no longer be limited to investigating only the most serious indictable offences.

The threshold for corruption inquiries is also likely to be lowered, with the commission currently required to possess prima facie evidence of serious corrupt conduct before launching investigations.

The changes follow a report from the commission itself suggesting serious corruption could be falling through the cracks because the legal threshold for investigations was ''vague, too high and therefore liable to challenge in the Supreme Court''.

Both Dr Napthine and Attorney-General Robert Clark initially appeared to play down the concerns. At a press conference on Wednesday, Dr Napthine said the ''minor'' recommendations by the commission would be considered, flagging a ''tweaking'' of IBAC's powers.

But after being informed towards the end of his morning press conference that Mr O'Farrell had quit as NSW premier over revelations in the NSW Independent Commission Against Corruption, the Premier strengthened the government's position.

''We have introduced an anti-corruption commission; they have said that their establishment was solid and sound. They have recommended further improvements, we will adopt those recommendations,'' Dr Napthine said.

After initially saying the recommendations would be ''considered'', Mr Clark told ABC radio the government would accept each of the recommendations, and intended to introduce legislation before the election. He said the timing of Mr O'Farrell's resignation and the response to IBAC was ''purely coincidental''.

Dr Napthine said Tuesday's report was the first time he had learnt of IBAC's ''specific'' concerns about the inadequate powers, maintaining that the body's first year of operation was ''a good first step'' and claiming it had been established on the ''best advice possible''. But a spokeswoman for IBAC said the Commission had ''publicly foreshadowed'' recommendations in relation to the legislative regime since its first special report to Parliament in November. ''This has been the subject of discussion with numerous stakeholders,'' she said.

The Victorian Coalition promised to establish a NSW-style commission at the 2010 election. Although the government had promised it would begin in July, 2011, it was not operational until February, 2013, amid strong criticism from legal experts, the Auditor-General and the Ombudsman that it lacked legislative bite, undermined the independence of other integrity agencies and created excessive bureaucracy.

Shadow attorney-general Martin Pakula said there was a clear and stark difference between the work of ICAC and IBAC, and said Labor, if elected, would fix the deficiencies in the Victorian body.

''The time for action hasn't just come, it has well passed,'' he said. ''Everybody said that the IBAC legislation was deficient, and Denis Napthine and his government simply refused to listen. And now what we have got is this sad, toothless, anti-corruption regime and the contrast between it and NSW has never been more stark.''