Decorated war veteran Ben Roberts-Smith has lost a court bid for his lawyers to quiz his ex-wife about confidential information in an email account.

Mr Roberts-Smith, in a long-running defamation action, is suing The Age, The Sydney Morning Herald and The Canberra Times over media reports from 2018 related to his deployments in Afghanistan that he says paint him as a war criminal.

In separate proceedings, Mr Roberts-Smith took action last year against his ex-wife Emma Roberts – who was slated to testify for the media outlets in the civil trial – to examine her over compliance with orders to hand over confidential information from an email account belonging to the SAS veteran.

He claims she handed over private and confidential communications to the mastheads in preparation for the defamation trial.

Both proceedings are in the Federal Court.

In a judgment delivered on Friday, Justice Robert Bromwich said Mr Roberts-Smith claimed Ms Roberts accessed his “RS Group Australia” email account, then passed on information for use in the defamation case.

“The crux of all this is that Mr Roberts-Smith believes that the notice to produce in the defamation proceedings was informed by confidential information of his that was provided to the respondents in those proceedings by Ms Roberts,” Justice Bromwich said.

However, the judge said Mr Roberts-Smith failed to prove a “sufficient basis” to examine Ms Roberts over her delivery to the court of any information obtained from the RS Group email account.

Justice Bromwich said there were also insufficient grounds to join Ms Roberts’ close friend Danielle Scott, and her husband, to the action.

Ms Scott, like Ms Roberts, is set to testify for the newspapers against Mr Roberts-Smith in the defamation trial, according to the judgment.

The judge said, in his view, Mr Roberts-Smith’s case failed to go beyond “bare possibilities and suspicions, with many such assertions in relation to Ms Roberts being shown to be ill-founded”.

The claims against Ms Scott were “equally ill-founded”, the judge said.

“Both Mr Roberts-Smith’s interlocutory application for the examination of Ms Roberts, and his interlocutory application to join Ms Scott and her husband must be dismissed,” he ruled.

Mr Roberts-Smith’s barrister Arthur Moses QC previously told the court that an email account used by Ms Scott or her husband accessed the war hero’s password-protected account at least 101 times between January 20, 2020, and May 7, 2021.

Justice Bromwich ordered Mr Roberts-Smith to pay Ms Roberts’ costs and adjourned the matter to January 28 for case management.

-AAP