Up to 30 public service employers – including Malcolm Turnbull's own department, the giant Human Services Department and the Australian Taxation Office – are insisting on removing the right of their workers to take time off if they are victims of family violence.

But the government says it is false to suggest that victims of violence will be unable to get time off work, saying employees in crisis can use miscellaneous leave provisions.

Anti-violence campaign group White Ribbon Australia said that all employers should be supporting victims of domestic abuse with specified leave entitlements, while a leading workplace academic says the removal of these rights is directly at odds with the government's rhetoric on violence against women.

Unions say the changes are being forced on the individual employing agencies by the Australian Public Service Commission, which is determined that public servants should win no "enhancements" to their conditions during the present round of enterprise bargaining.

Mr Turnbull's Department of the Prime Minister and Cabinet refused a request by the CPSU union to include domestic violence leave in its latest draft agreement, claiming it was an "enhancement" to workplace conditions and banned by the bargaining rules, according to the union.

The old FaHCSIA department, much of which has been swallowed up by PM&C, had a provision through which the departmental boss could approve leave in certain circumstances but the Prime Minister and Cabinet negotiators want this clause gone too, describing it as an enhancement.

But a PM&C spokeswoman said on Tuesday that departmental employees could access miscellaneous leave, with the permission of their manager, if they experienced domestic violence and there were no plans to change these arrangements in the new enterprise agreement.

At the Fair Work Commission, an early draft of the commission's proposed EA came back from the Public Service Commission with domestic violence leave crossed-out, the union says, with the APSC insisting it was an "enhancement".

The Fair Work Commission said on Tuesday that there had been "no specific instructions" to remove the clauses.

Senator Cash's office said on Tuesday that APS employees facing trouble in their personal lives could access a number of leave types and other provisions in existing and new enterprise agreements and there were no plans to change theses arrangements.

Sue Williamson, a lecturer in human resource management at the University of NSW Canberra, said the approach to bargaining seemed to fly in the face of the government's pronouncements on domestic violence.

"Some of these clauses were only included in the last round of agreements and the reasons for their removal are not publicly known," Dr Williamson wrote in an article for The Canberra Times.

"Coupled with the Prime Minister's stated commitment to reducing violence against women, the removal of this clause appears to undermine government policy."

Jessica Luter from White Ribbon Australia said the foundation wanted all workplaces to support victims of domestic violence.

"We believe that domestic violence is both a human rights issue and a workplace issue," Ms Luter said.

"If a person is affected by domestic violence in their home life, it most likely will affect their working life as well.

"So it is incredibly important that organisations support their employees if they are victims of violence and one of those things is domestic violence leave."

Ms Luter said more than 100 organisations had joined the White Ribbon workplace accreditation program, with another 800 expressing an interested in joining, but could not say if any of them were federal government agencies.

But the availability of domestic violence leave had to be at least considered before an employer could be accredited.

"We highly recommend that domestic violence leave is put in place," Ms Luter said.