The WA Government is trying to force the reappointment of anti-corruption boss John McKechnie.

The Government is introducing unprecedented legislation to reappoint the state's top corruption watchdog after his renewal was blocked by a parliamentary committee.

The CCC Commissioner’s appointment needs majority and bi-partisan support from the Joint Standing Committee on the Corruption and Crime Commission.

Premier Mark McGowan said new legislation would change the rules so that majority and bi-partisan support of the whole Parliament, and not just the committee, can be used 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.”

Opposition leader Liza Harvey says the Liberals will not support the “bizarre, rushed and dangerous” legislation.

“These proposed laws will give the premier - any premier now or future, honest or corrupt - the ability to choose the top corruption fighter in WA,” she said on Wednesday.

“That is dangerous. It goes against all good anti-corruption practices.”

The CCC is currently investigating the misuse of electoral allowances by several MPs, including Liberal members.

In a report last year, attorney general John Quigley alluded to MPs attempting to “stymie (the CCC) investigation of their expenses”.