A scathing report from the solicitor-general has found that while Scott Morrison did not break the law with his power grab of the resources portfolio, he “fundamentally undermined” the principles of responsible government by doing so.

Prime Minister Anthony Albanese released the solicitor-general’s official legal advice into the former PM’s secret appointment as resources minister on Tuesday.

It found Mr Morrison ran roughshod over core aspects of Australian democratic government, including a standard of responsible government contained in the constitution, and may have even sought to cover his tracks.

This was not a theoretical problem for the government, the PM said.

Mr Albanese said it involved acts that changed the way a large government grants scheme worth hundreds of millions of dollars was run, and which are being argued as grounds for appealing a decision on a gas exploration project.

“That goes to the use of taxpayer funds as well and the potential implications to taxpayers of the structures that were established,” he said.

Mr Albanese said a further inquiry would examine all five of the Morrison government’s secret ministerial arrangements in greater detail. Arrangements for that inquiry will be made at a future date.

The PM said the report had identified many concerns had been raised about the previous government’s lack of transparency in power, including a question of whether Mr Morrison sought to cover up his power grab before it began.

“There are clearly a whole raft of questions which have been raised,” he said.

But Mr Albanese said more time and information was needed to understand what had happened.

The report concludes Mr Morrison’s self-appointment as resources minister, at the same time as the portfolio was held by the Nationals’ Keith Pitt, was valid. But by serving in that office in a capacity unknown to the public or parliament, constitutional principles of responsible government were ignored, the report found.

It said that in having two ministers occupy overlapping portfolios secretly, Mr Morrison crossed the wires of the legal model for responsible government on which decisions are made by cabinets and ministers in Australia.

Not only were affected ministers bypassed but so too were the public and senior figures at the top of government, an arrangement so shrouded in secrecy that it almost became self-defeating, the report said.

“Failure to inform at least the secretary of the department of the appointment therefore defeats the purpose of the appointment,” the report concluded.

One tradition Mr Morrison breached with real world implications was a departure from a half-century old format for declaring a list of ministries to the parliament.

Under changes introduced shortly after Mr Morrison came to power, the ministry was list was restructured and reworded in a way that concealed the nature of cabinet ministers’ appointments.

“The impetus for the inclusion of those words is unclear, although it seems possible that they were included so as to ensure that the tabling of the ministry list did not mislead parliament,” the report said.

Mr Albanese noted that the departure from practice with the ministerial list was a change that had gone unnoticed but which had serious implications.

“It’s one of the reasons why we need more information; there’s a need for more transparency about how this occurred,” he said.