Speaking at the National Press Club, Transparency Australia chief executive Serena Lillywhite said while a federal integrity commission was not a silver bullet to stamp out corruption, its need was urgent.

"It is a unique, potentially once-in-a-generation time to actually actually design a cohesive integrity framework that has a robust integrity commission as its linchpin," she said.

"It is a no-brainer. We need one, and more than 80 per cent of Australians want one."

While the government at the 2019 election pledged to establish a federal integrity body, the coalition has attracted criticism for not introducing legislation to parliament during the current term.

Prime Minister Scott Morrison said the government would introduce the legislation if Labor supported the move.

Government MP Bridget Archer crossed the floor of parliament last week to back an independent push to bring debate on the issue.

Ms Lillywhite said she commended the stance taken by Ms Archer in parliament.

"Last week's extraordinary scenes in parliament laid bare for all to see the resistance to introducing or even debating a strong integrity commission."

Prominent lawyer Geoffrey Watson from the Centre for Public Integrity said the commission needed to be powerful.

"The predatory misuse of ministerial discretion in allocating money is not a rumour, it is an objective fact," he told the National Press Club.

"(The commission) needs to have its powers applied equally to all and it must be opened to scrutiny through a parliamentary oversight committee or through judicial review. "

The government's version of the commission, which has been released as an exposure draft, has been criticised as weak.

While some have urged the federal body to have the powers of NSW's Independent Commission Against Corruption, Mr Morrison described it as a kangaroo court.

Liberal senator Concetta Fierravanti-Wells said in a speech to the upper house an analysis of the proposed federal commission found it would be the "weakest and least effective integrity agency in the country".

"Those who resist the introduction of an effective federal integrity body raise people's curiosity," she told parliament.

The prime minister tabled the proposal in the House of Representatives when asked about the senator's comments, but declined a Labor invitation to immediately bring on the bill for debate.

"We have done the work to ensure an effective integrity commission can be implemented in this country," Mr Morrison said.

"There is only one obstacle to that being passed in this parliament: the Labor Party."

Pauline Wright from the NSW Council for Civil Liberties also said the commission needed stronger powers than were already proposed.

"Under the government's model, investigations can't even begin unless a high bar is reached of reasonable suspicion of one of the specifically defined crimes in their model," she said.

"Such a limited scope would be unconscionable. While criminal conduct should, of course, be a priority for any anti-corruption body, it should be able to investigate other forms of misconduct."

Australian Associated Press