The federal government has narrowly defeated an attempt by the Senate crossbench, Greens and Labor to kickstart a debate on a national integrity commission.

Complicated Senate voting rules, forced by the absence of some Senators due to COVID-19 restrictions, resulted in a tied vote on the motion of 25 to 25.

Despite not being present in the chamber, One Nation sided with the government, shifting the numbers on the floor and ultimately defeating the motion.

The Coalition has been widely criticised for not having introduced its proposal to Parliament, given it was first flagged by Prime Minister Scott Morrison in late 2018.

South Australian independent senator Rex Patrick tried to suspend the business of the Upper House on Tuesday afternoon to bring on the debate on the crossbench integrity commission bill.

Parliament is still waiting to see the revised model from Attorney-General Michaelia Cash.

"They made that as a promise as they went into the last election.

"You get to a point where you say, 'Sorry, you can't have us wait any longer'."

Former attorney-general Christian Porter's model, revealed in 2018, was labelled as highly secretive and lacking the strong investigative powers needed to stamp out corruption.

Labor backed Senator Patrick's attempt to force the issue onto the agenda, arguing the Senate needed to "take charge" of the debate given the Coalition's delays in introducing its proposal.

"This eight-year-old, tired government — there are plenty of reasons why they don't want to get to a debate around a national anti-corruption body today, or any day, leading up to the next election," Shadow Finance Minister Katy Gallagher told the chamber.

"That's because of the litany of scandals, rorts, waste and mismanagement that this government has presided over and it would make them vulnerable.

"1,077 days ago, this Prime Minister promised — and we know he's not very good with telling the truth — promised to put one in place and we are still waiting."

The Greens have long campaigned for an anti-corruption commission, arguing the Coalition has been kicking the issue down the road.

"Consultation after consultation, which keeps getting ignored, and they still have a weak, pathetic body that has been criticised by experts as acting like a protection racket for their own MPs rather than a watchdog to clean up politics and to genuinely dissuade corruption," Greens Senate leader Larissa Waters said.

"I looked at the figures, half of the Cabinet have been embroiled in an integrity scandal over recent years.

"It is no wonder the government doesn't want to bring on a bill for a corruption watchdog – they'd lose half their Cabinet."

Tasmanian Independent Senator Jacqui Lambie took aim at the government's delays, in her unique style, telling the Upper House a child born when the Coalition first committed to a national integrity commission would now be almost three years old.

"She's learned to crawl, to stand up, to walk, she's pretty much getting ready for pre-school now and she's probably learning to count," she 

"You know what, that baby's made more progress in 1,000 days than the Liberal party have on their own bill. Shameful, shameful!"

Opponents accused of distorting reality

The Leader of the government in the Senate, Simon Birmingham, accused the Coalition's political opponents of distorting reality.

"It often seems that when those opposite and those on the crossbench speak about matters in relation to a proposed Commonwealth Integrity Commission, or other names that others seek to give such entities, that they do so with some belief that there is a void that exists in relation to accountability, to process, to oversight," he said.

"That is quite clearly not the case.

"We're not going to suggest that we should simply adopt — as Senator Patrick's motion seeks to do — in the space of an hour and a half a model that has not been subject to the same type of rigour, thoroughness and analysis that the Attorney-General has been working through."

In defeating the motion, parliamentary debate over an integrity commission may not happen until after the next election.

If the Prime Minister calls an election for March next year, MPs and Senators will not return to Canberra before hitting the hustings.

Senator Patrick is seeking re-election, running as an independent after breaking away from the Centre Alliance party in South Australia.