The WA Government will introduce unprecedented legislation in a bid to reappoint the state's top corruption watchdog, after his renewal was blocked by a parliamentary committee.

Key points: The CCC boss can only be reappointed with bi-partisan committee support

The CCC boss can only be reappointed with bi-partisan committee support But the committee has not been able to ratify the reappointment

But the committee has not been able to ratify the reappointment The CCC uncovered some of WA's biggest scandals with Mr McKechnie at the helm

Corruption and Crime Commissioner John McKechnie's term is due to expire on April 28, but the WA Premier said Mr McKechnie was unable to be reappointed because the committee would not ratify his reappointment.

The CCC Commissioner must receive majority and bi-partisan support from the Joint Standing Committee on the Corruption and Crime Commission.

Premier Mark McGowan said he would introduce new legislation that would require majority and bi-partisan support of the whole Parliament, and not just the committee, to reappoint the CCC boss.

"The fact that one member of one committee can stop his reappointment is, frankly, wrong," he said.

"The easy way of overcoming this is simply to bring in a very straight-forward piece of legislation.

"We'll request that the Opposition support [the Bill's] passage this week, if they don't we'll have to bring it back for further debate in three weeks' time."

The committee is made up of Labor MPs Margaret Quirk and Matthew Hughes, Liberal MP Jim Chown and Greens MP Alison Xamon.

It is not known whether one or more MPs did not agree to the Commissioner's reappointment.

Mr McGowan said he last week wrote to the Opposition Leader, Liza Harvey, to seek her support for Mr McKechnie's reappointment.

"Unfortunately, the leader of the opposition and the Liberal Party have not decided to assist in Mr McKechnie's reappointment thus far," he said

"I will leave it to them to explain why."

Bill to be introduced this week

During Mr McKechnie's time as commissioner, the CCC has uncovered some of the biggest public sector corruption scandals including within the Department of Communities and the North Metropolitan Health Service.

The CCC also last year released a report into the alleged misuse of electoral allowances in the WA Parliament — which detailed how former Liberal MP Phil Edman used taxpayer funds to pay for strippers and travel for sex.

Mr McGowan said the Commissioner's reappointment was a no-brainer.

"Mr McKechnie was the outstanding candidate recommended by an independent committee, which is chaired by the Chief Justice of the Supreme Court, and also had as a member the Chief Justice of the District Court," he said.

"His work in rooting out corruption has been second-to-none.

"So clearly, we're just trying to get the best person into the job, in the interest of Western Australia," he said.

"I might also add, the people who don't want Mr McKechnie reappointed are the crooks and criminals out there.

Legislation 'not steamrolling': Attorney General

Attorney General John Quigley dismissed claims the new legislation was an attempt to steamroll the Commissioner's reappointment through Parliament.

Attorney General John Quigley said the current legislation was flawed. ( ABC News: Hugh Sando )

"What you've got to remember, is that the committees of Parliament are subservient to the Parliament as a whole," he said.

"They are just committees of the whole of the Parliament.

"There is a flaw in the legislation in that it requires a majority of the committee, yet the committee is made up of four people."

Mr Quigley said the same committee had, in 2017, recommended amendments to remove it from the decision-making process.

Work with the committee, Harvey says

Opposition leader Liza Harvey said she unequivocally supported Mr McKechnie, but that changing legislation was unnecessary.

"There's been some horrendous but outstanding investigations into a number of agencies and departments, and indeed a former member of Parliament, and I think that work is very important," she said.

"With respect to the legislative response that the Premier and the Attorney General have suggested, changing the entire Act around the reappointment of this commissioner, I think it's unnecessary.

"I think there are two acting commissioners who can fulfil the role while the Premier works this out with the joint standing committee."

Ms Harvey said the proposed legislation changed the intent of the legislation as it had been designed.

"My very strong view is that, if the Premier would sit down with those four people on the committee, and negotiate with them, that he might get the outcome he wants to achieve without having to rush through legislation," she said.