By Kat Wong in Canberra

The head of the federal anti-corruption watchdog has come under fire over the fallout of the former coalition government’s unlawful debt collection scheme.

National Anti-Corruption Commission head Paul Brereton faced a parliamentary inquiry on Friday after the watchdog decided not to investigate six people associated with robodebt.

In October, the National Anti-Corruption Commission Inspector Gail Furness found the commissioner engaged in misconduct as he had ties with one of the six in question but did not adequately recuse himself from the decision.

Mr Brereton recognised he had “prior professional associations” with one of the subjects of referral but wanted to balance his responsibilities as a commissioner with a perception of bias, so he delegated the final decision to the deputy commissioner and excused himself from the meeting the decision was made.

“I considered it would have been irresponsible and negligent for me, as a leader of the organisation, to abandon any involvement, provide no guidance, walk away, say it was ‘not my problem’ and leave everyone else to their own devices,” he told the inquiry on Friday.

“I accept that through the lens of the legal notion of apprehended bias, I have been found to have made a mistake, for which I am solely responsible.”

“I got that balance wrong, we’re now setting about putting that right.”

But there is a difference between real bias and the inspector’s finding of “apprehended bias”, where a reasonable observer might believe a decision maker is not impartial, Mr Brereton maintained.

“There is no suggestion of actual bias, nor of any intentional impropriety,” he said.

“There is no reflection on my integrity, the mistake is characterised by the inspector as an error of judgment.”

Resourcing, and the commission’s inability to provide a remedy or impose sanctions, were key considerations in the commission’s decision not to pursue the robodebt investigation.

“If we investigated robodebt, there would be other things that we would not be able to investigate,” Mr Brereton said.

“We’ve never said there is no value in it.

“But when you look at the balancing, all the considerations, the value in simply adding a stamp of corrupt conduct to the conduct that had been found by the robodebt royal commission would not advance the public interest.”

The robodebt royal commission’s final report, handed down in July 2023, painted a scathing portrait of a scheme that was unfair, unreasonable and targeted some of the most vulnerable Australians.

It automatically calculated debt by averaging an individual’s income, but this often failed to accurately reflect their earnings and many welfare recipients were falsely accused of owing the government money.

Between 2016 and 2019, the former coalition government’s illegal scheme recovered more than $750 million from almost 400,000 people.

Robodebt was later linked to several suicides.

The anti-corruption commission’s decision not to investigate the six public servants tied to robodebt will be reconsidered by an independent person after a recommendation from Ms Furness.

The commission has also amended its conflict of interest procedures to prevent similar situations from occurring in future, Mr Brereton said.