It was "legally unreasonable" for the Australian Federal Police to seek a warrant to raid the ABC and for a court registrar to issue it, a court has heard.

Key points: Federal Police used a search warrant to access electronic files related to stories known as the Afghan Files

Federal Police used a search warrant to access electronic files related to stories known as the Afghan Files The ABC is asking the Federal Court to declare the warrant invalid

The ABC is asking the Federal Court to declare the warrant invalid It's also asking for a permanent injunction to stop the AFP accessing the electronic files

AFP officers spent more than eight hours at the broadcaster's Ultimo headquarters in early June conducting raids over a series of stories known as the Afghan Files.

The stories, published in 2017 by investigative journalists Dan Oakes and Sam Clark, were based on hundreds of pages of leaked Defence documents and revealed allegations of unlawful killings and misconduct by Australian soldiers in Afghanistan.

During the first hearing since the ABC's legal challenge to the warrant was launched in June, barrister Dr Matthew Collins, QC, told the Federal Court of Australia in Sydney that the terms of the warrant were excessively broad.

Dr Collins said the subject matter included terms such as "the ABC", "the Australian Defence Force" and "Afghanistan", and only one of the three included conditions, placed any meaningful limitations on the warrant.

He said the leaked documents were historical rather than current in nature and disclosed allegations of "inarguable public importance".

Warrant went "well beyond" its purpose

Court documents have previously revealed the police officers who raided the Ultimo headquarters were searching for evidence — including fingerprints — to prove that an ABC reporter had committed criminal offences.

Proceedings against the man accused of leaking the files, David McBride, are underway in the ACT Supreme Court.

His trial may take place in 2020, the Federal Court heard.

Dr Collins said the warrant went "well beyond" the purpose of seeking to confirm admissions made by Mr McBride.

Justice Wendy Abraham set the matter down for further argument on August 19.

An undertaking given by the AFP not to access the seized files until the court challenge is determined was extended.