Labor is calling time on how the federal government hands out grants amid renewed scrutiny on the coalition's condemned commuter car park scheme.
Labor finance spokeswoman Katy Gallagher will introduce an "anti-rorting bill" to parliament on Wednesday.
It would allow the public to see how ministers make decisions about where taxpayer money is spent.
"There have been sports rorts, regional rorts, safer seats rorts and, most recently and perhaps most egregiously, the 'pork and ride' commuter car park rorts," Senator Gallagher said.
Labor wants the laws passed by December so Prime Minister Scott Morrison cannot "buy votes and win an election", she said.
The bill would require ministers who approve grants rejected by their departments, or who award grants in their own electorates, to report the decision to the finance minister within 30 days.
The reports would then need to be tabled in parliament within five sitting days to improve accountability and transparency of government decisions.
"This will dramatically reduce the time ministers are able to hide their dodgy decisions from the Australian community from up to 16 months down to just a couple of months," Senator Gallagher said.
Should the bill pass the Senate in the coming months, it will be up to the Morrison government to allow debate on it in the lower house.
One of the bill's targets is the coalition's commuter car park scheme condemned in an auditor-general's report.
It found the $660 million pre-2019 election car splash was poorly administered and projects were not based on need.
Then-urban infrastructure minister Alan Tudge's office started with a "top 20 marginals" list, the Australian National Audit Office said.
Mr Tudge, who now holds the education portfolio, on Wednesday said the car park sites were chosen based on need.
"And most of those were based in Melbourne where the need was the greatest," he told reporters in Canberra.
Mr Tudge also said he was not aware of the "top 20 marginals" spreadsheet.
