Assistant minister to the attorney-general Amanda Stoker said the government would strengthen, streamline and enhance whistleblower protections.

"The Australian government is absolutely committed to the principle of a free press and has a comprehensive reform agenda for enhancing trust and accountability in the public sector," she told a whistleblower forum on Thursday.

"Ensuring the integrity of our public institutions is critical to democracy. Trust and confidence in our democratic institutions has never been more important."

Senator Stoker said the plan to amend whistleblowing laws would mean only supreme or federal court judges could issue warrants against journalists for publishing sensitive material, and an advocate would be appointed to lobby the judge on behalf of the journalist.

The general secrecy offence will be removed under the proposed reforms, which criminalises the leaking of secret information.

Better legal advice about disclosures will also become available for whistleblowers and it will be made explicit that the regime covers former public officials.

Department heads will have additional obligations to help employees make disclosures and greater protections will be carved out for whistleblowers.

Protections will be expanded to cover people associated with a whistleblower.

Greater powers will also be given to the Commonwealth Ombudsman and the Inspector-General of Intelligence and Security.

Disclosures about employee grievances, such as being passed over for a promotion, will be carved out of the current act.

"This will free up agencies' valuable resources to focus on allegations of more serious wrongdoing," Senator Stoker said.

Senator Stoker talked up the government's track record of protecting whistleblowers a day after it doubled down on having secret evidence held against the former lawyer of Witness K, Bernard Collaery.

Lawyers acting on behalf of the attorney-general argued to change secret evidence in Mr Collaery's trial that neither he nor his lawyers have been able to see.

The government is prosecuting Mr Collaery for allegedly sharing classified information about the bugging operation of the East Timor prime minister by Australian officials in 2004.

The government tried to keep the trial from public view, a push which was overturned by the Court of Appeal.

Senator Stoker also reaffirmed the government's commitment to a federal integrity commission.

The government's proposed commission has been criticised for being toothless.

Public servants, politicians and their staff would be allowed to give evidence in private and only government agencies would be able to refer matters to the government's proposed commission.

It has also been criticised for having a narrow definition of corruption and too high a bar to start investigations.

The government has promised laws to set up the watchdog will be introduced to parliament this term.

Australian Associated Press