Government Services Minister Bill Shorten has accused Morrison government minister Stuart Robert of misleading the Australian public after his bombshell evidence to the robodebt inquiry.

Mr Robert was the minister who oversaw the controversial Centrelink debt recovery program in the final days before it was declared illegal.

Giving evidence at the royal commission into the scheme on Thursday, he admitted making false statements to support the scheme.

“I had a massive personal misgiving, yes. But I’m still a cabinet minister,” he said of his personal position while presiding over the automated debt-recovery program in 2019.

On Friday, Mr Shorten described Mr Robert’s evidence as “peak bizarre”, and said the former minister had revealed his misleading statements only because of he was required to be truthful at the royal commission.

“Because Mr Roberts has landed this big issue in his lap, [Opposition Leader Peter] Dutton will have to say if he thinks that cabinet solidarity allows you to mislead the Australian people,” he told ABC TV.

“I think there must be a lot of former Coalition ministers who would think when, given this fact situation, that cabinet solidarity, can be stretched – but this has been stretched far further than anyone has tried before.”

In his evidence on Thursday, Mr Robert cast himself as the man who brought robodebt to a swift end after his conscience was pricked by a report into the scheme.

“Within hours I walked into the prime minister’s (Scott Morrison’s) office to put an end to it,” he testified.

“I think my actions go to my state of mind.”

Mr Robert’s evidence contradicted that of two of Canberra’s top public servants who worked closely with him as they oversaw the scheme – the human services department’s chief lawyer and top bureaucrat.

Former department secretary Renee Leon told the inquiry this week that Mr Robert dismissed legal advice from the solicitor-general in 2019 that the scheme was unlawful.

When she presented him with the findings, Professor Leon recalled Mr Robert telling her: “Well, secretary, legal advice is just advice.”

But Mr Robert rejected this claim and said he presented the advice to Mr Morrison “within hours”.

In media appearances afterward, Mr Robert continued to defend the scheme because it was still the government’s policy.

“If I’ve got a personal opinion, my next step is to seek the appropriate advice,” he told the inquiry on Thursday.

“Until such time as that arrives, I remain a cabinet minister, and I’m responsible for holding the cabinet line.”

Commissioner Catherine Holmes asked if that included misrepresenting policies to the Australian public.

Mr Robert said he “wouldn’t put it that way” because his personal opinion could be wrong until proven otherwise by the solicitor-general.

Liberal senator Marise Payne appeared before the commission for a second time on Thursday. She was asked how the robodebt proposal, originally flagged as requiring legislative changes to go ahead, was later presented to cabinet as not needing any changes.

Senator Payne was human services minister between 2013 and 2015 when the scheme was being established as a new policy.

She said she was told, more than once, that the two departments tasked with overseeing the scheme were working through any legislative changes.

“There was not a red flag or a stop sign placed in front of me, to the best of my recollection,” she said.

Meanwhile, former social services department branch manager Emma Kate McGuirk was asked to clarify her knowledge of the use of income averaging as a last resort to raise debts.

Ms McGuirk previously gave evidence in November that she did not know the human services department had used that method until 2017.

But an email discovered by the commission from 2015, when Ms McGuirk worked as a director in human services, indicated otherwise.

“As long as the customer is given the opportunity to correctly declare against each fortnight and apportionment is the last resort, we support what you are doing. Good luck!” the email from Ms McGuirk to another public servant said.

Ms McGuirk said she couldn’t find the email when she was preparing her statement. It later emerged the 2017 email trail alerting her to the 2015 advice was sent to the wrong address and therefore did not come up in her search.

-with AAP