Labor has backed calls for an extension of the Disability Royal Commission, as it ramped up pressure on the Morrison government to urgently pass stronger protections for witnesses providing evidence to the inquiry.
Commission chair Ronald Sackville last year requested a 17-month extension to the timeframe for handing down his final report, as he tabled an interim report that found people with disabilities experienced violence, abuse, neglect and exploitation across "all aspects of their lives".
In making the case for an extension, Mr Sackville has repeatedly argued that an inquiry examining mistreatment of Australians with a disability was a "marathon, not a sprint".
A 17-month extension would see the final report handed down in September 2023, rather than April next year.
The chair has reportedly written twice to the federal government to request an extension - without receiving a response.
Labor's shadow Attorney-General, Mark Dreyfus, and NDIS spokesman, Bill Shorten, have now supported calls for an extension, due to the commission's broad terms of reference and the disruptions caused by the coronavirus pandemic.
The government was non-committal about granting an extension on Monday. A spokesman for acting Attorney-General Michaelia Cash said a decision would be announced in "due course".
Mr Dreyfus and Mr Shorten also used their letter to Senator Cash and Prime Minister Scott Morrison to demand the urgent introduction of privacy protections for people giving evidence to the commission.
While Mr Porter had asked his department to work "swiftly" to draft amendments to the Royal Commissions Act, legislation has yet to be presented to federal parliament.
In their letter, the Labor frontbenchers said the absence of the privacy protections was undermining the inquiry.
"Many people with disability who would like to make submissions to the Disability Royal Commission do not have confidence that their privacy will be protected," the letter said.
The Labor pair said the government must either pass its legislation or support a separate bill introduced by Greens senator Jordan Steele-John before the end of this week, to ensure potential witnesses weren't denied protections any longer.
The government last month refused to support Mr Steele-John's proposal, a position Labor has described as "indefensible".
After this week, both houses of parliament won't sit until May.
"[if laws aren't passed] many Australians with disability will have to wait at least another six weeks before the parliament does what is needed to give them confidence to come forward and tell their stories to the royal commission," the letter said.
"We trust you will address these matters urgently."
Ms Cash's spokesman said the government hoped to introduce the amendments in March.
The spokesman said in the meantime the commission could protect witnesses in a number of ways, including using private sessions, pseudonyms or the "making of do not publish orders".
"It is clearly a matter for the royal commission as to how it applies these protections," the spokesman said.