Facing the royal commission on Tuesday, ex-secretary of the Department of Human Sevices Renee Leon said that after receiving advice from the Solicitor-General, she advised Mr Robert that the scheme should be scrapped in October 2019.

When she raised the issue again in November 2019, Ms Leon said she recalled advising Mr Robert with words to the effect of: "The best course is to apologise to our customers, to admit the error, and to inform customers and staff of the steps we will take to correct the error."

Ms Leon said Mr Robert did not accept her advice, responding with words to the effect of: "We absolutely will not be doing that. We will double down."

"He said it confidently and firmly, I have a very strong memory of it because I was so surprised and shocked," Ms Leon told the robodebt royal commission on Tuesday.

"I thought my advice was obvious, really that there wasn't any other course to take that it seemed the only thing for an organisation that had been found to be doing something unlawful to cease doing it and to remediate and to apologise."

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