Senior Liberals are at odds over the merit of a further inquiry into former prime minister Scott Morrison's secret ministerial appointments.
Prime Minister Anthony Albanese is working on the details of an inquiry - headed by an eminent legal figure - into his predecessor's decision to secretly swear himself into five ministerial portfolios between 2020 and 2021.
The solicitor-general this week released legal advice saying while the appointments were valid, they were inconsistent with constitutional conventions and at odds with responsible government.
Opposition foreign affairs spokesman Simon Birmingham said the inquiry should examine the role of a wide range of people involved in the decision-making process.
"It should look at the role of others in terms of advice and the like that's been provided," he told ABC Radio on Thursday.
"I want to make sure that the same types of mistakes can't happen in the future and that there is transparency around who is able to administer different departments at different points in time."
Senator Birmingham said he expected those involved in the ministerial process to have had some concerns about Mr Morrison's secret roles.
"I would have thought there should have been questions asked down the track when we got to appointments in things such as Treasury and home affairs more than a year later," he said.
He said the decision for Mr Morrison to take on the health portfolio, given the concerns around the COVID-19 pandemic, was entirely defensible and logical.
"The only error on that part was that it wasn't made public."
Former home affairs minister Karen Andrews, who has called on Mr Morrison to resign from parliament over the controversy, said she wasn't convinced an inquiry was needed due to there being enough information already made public.
"What's the point in going further and trying to find out who knew what, when the issue really is what needs to be done to make sure that it never happens again?" Ms Andrews told Sky News on Thursday.
"Let's focus on the issues at hand. We know enough to deal with this issue."
While there have been calls for Mr Morrison to be referred to a powerful parliamentary privileges committee over the controversy, such attempts have been rejected by House of Representatives Speaker Milton Dick.
Mr Dick is understood to have said there wasn't enough evidence to refer Mr Morrison to the privileges committee on the grounds he misled parliament.
