Stephen Charles, a member of a non-partisan group of former judges campaigning for an effective federal integrity commission, said he could name around 20 issues worthy of investigation, citing as examples the so-called Watergate affair, the government's $423 million contract with the little-known company Paladin for security on Manus Island, the events leading up to the approval of the Adani mine and allegations about rorting in defence procurement.

Labor and crossbenchers have endorsed a model for a powerful federal body that could investigate such matters, but the government has outlined its own model, which it calls the Commonwealth Integrity Commission, which judge Charles believes is designed to fail.

"The Coalition's proposed Commonwealth Integrity Commission is a fraudulent nonsense, designed to protect ministers, parliamentarians and their aides from investigation and exposure," the former Victorian appeals court judge said.

"The Coalition does not dare to debate this with the Opposition, because the proposed CIC could never properly investigate or discover any federal corruption nor could it expose any corruption it might accidentally discover."

Attorney-General Christian Porter dismissed the claim, saying unlike Labor it dedicated funding to the creation of an integrity commission, and provided a letter to Labor offering to debate the issue.

He said it appeared Labor wanted to introduce a federal version of the NSW ICAC with "all its obvious failings", but that in its costings it had not dedicated funding to such a body.

"The idea the Labor Party has no integrity concerns - the party of Sam Dastyari, the party of the CFMEU, the party of Eddie Obeid, Joe Tripodi and Kristina Keneally, the party of the red shirts scandal, the party whose current candidate for the seat of Petrie is connected to a current Queensland Crime and Corruption Commission investigation- is partisan rubbish," Mr Porter said.

The government's proposed CIC would be broken into two divisions; one called the "law enforcement division" would cover agencies such as the Federal Police and the Border Force, and another division with jurisdiction over parliamentarians and their staff, public service departments and agencies, though not over the judiciary nor outsiders at large dealing with federal agencies, including businesses accepting government contracts or their lobbyists.

According to judge Charles the operations of the first division are largely already conducted by an existing body, while the second division - with jurisdiction over politicians and their staff - would be granted so little authority it could not act as an anti-corruption commission.

Further, CIC hearings would be held in secret with the public only allowed to know of investigations after the fact and if there were prosecutions. Had the royal commission into malfeasance in the finance sector been held under such constraints, the public would not have known today that it had happened, judge Charles said.

"The Coalition has clearly decided to ensure that there is no effective anti-corruption commission created to investigate the public service, ministers, parliamentarians or their staff," he said.

"The Coalition's proposed CIC is dressed-up to look like an anti-corruption commission, which it is not. The CIC is a sham, and should be exposed as such."