Prime Minister Tony Abbott’s use of parliamentary privilege to denounce an alleged terror attack not yet proven in court has been criticised by legal experts.

Despite the long-standing tradition of ‘innocent until proven guilty’, the Prime Minister publicly denounced Omar Al-Kutobi, 24, and Mohammad Kiad, 25, as being guilty of “monstrous extremism” and membership of a “death cult” in Parliament on Thursday.

Mr Abbott has not confirmed that he sought legal advice before quoting from a video allegedly produced by the two men, who face life in prison and are yet to have a bail hearing.

• Why tougher laws won’t stop ‘lone idiots’
• Abbott warns of ‘Kim Jong’ submarines for Oz

Instead, the Prime Minister’s office said Mr Abbott asked the Australian Federal Police commissioner for permission before telling the nation that the two men were “soldiers” of ISIS.

Some law experts say any future trial of the two men, who were arrested in Sydney’s west on Tuesday on terrorism charges, may be compromised.

President of the New South Wales Bar Association, Jane Needham SC, told the ABC that the airing of evidence in parliament might bias the jury.

“And that could mean that the men could not receive a fair trial, because the jury had already made up their minds, or that their trials might be stayed, and that has happened in the past where comments made in parliament have been the basis of a stay application later,” Ms Needham said.

Prominent Australian barrister Robert Richter QC also told the ABC he believed Mr Abbott’s “inflammatory” speech could be prejudicial.

“To make those sorts of inflammatory utterances is calculated to influence the judicial process and it’s being done for a political purpose,” Mr Richter said.

The video made public by Mr Abbott is reportedly likely to be used by prosecutors to fight an expected bail application on March 16.

In normal circumstances, those who publish sensitive material from a criminal trial risk being found in contempt of court, but the tradition of parliamentary privilege gives politicians immunity from legal consequences for what they say in parliament.

—with AAP, ABC