The Prime Minister's Digital Transformation Office was "locked out" of helping with Centrelink's robo-debt, the former head of the agency says.
Paul Shetler, who was handpicked by Mr Turnbull to lead the government's technological revolution, says he and his colleagues first heard about the automatically generated debt program in the media.
Mr Shetler has been an outspoken critic of the federal government's tech efforts since he resigned in November, just weeks after his agency was restructured and his job downsized.
The renamed Digital Transformation Agency has since been called in to try to get the robo-debt program back on track.
Centrelink, its parent department Human Services and its Minister Alan Tudge are all enduring a storm of criticism over the robo-debt debacle which has seen more than 230,000 clients targeted, many of them told that they owe money.
But Mr Shetler says his agency, which was supposed to help government departments get its technological efforts right, first heard about the "Employment Income Data Matching" policy through the media.
"I found out, and I think pretty much everybody in DTA pretty much found out about it when it was in the papers," he told ABC radio.
Mr Shetler said the approach was typical of the giant Department of Human Services.
"Generally speaking they were difficult to work with and very, very defensive...'nothing is wrong, everything is good, the house is burning down but everything is fine,'" he said.
Mr Shetler said his office's remit did not translate into reality in the complex world of Canberra's public service.
"It was sort of one of these things where they give you authority in name only but without any ability to do anything on it," he said.
"We had no idea what they were actually doing. We had no visibility into the product plan, we had no visibility into the development plans, we didn't know how they were testing it.
"We were just locked out."
But the minister in charge of digital transformation, Angus Taylor said projects like robo-debt were not in the original remit of the Transformation Office.
"That hasn't been the DTA's role," he told the national broadcaster. "The DTA's role initially has been to create platforms for other agencies to use.
"The role of the DTA is now changing and it's playing a significant role in oversight of all government projects but that that was a restructuring that was done very late last year and is going into place now."