US Justice Department has been unwilling to release even a heavily edited document as search warrant affidavits contain potentially revealing information about an investigation.

A US judge has agreed to make public heavily censored documents that supported the FBI's search warrant for former president Donald Trump's Mar-a-Lago estate.
A US judge has agreed to make public heavily censored documents that supported the FBI's search warrant for former president Donald Trump's Mar-a-Lago estate. (Jon Elswick / AP)

A US judge has ordered the Justice Department to make public a redacted version of the affidavit that supported federal agents' search of former president Donald Trump's Florida home to look for classified documents.

The directive from US Magistrate Judge Bruce Reinhart on Thursday came hours after federal law enforcement officials submitted under seal the portions of the affidavit that they want to keep secret as their investigation moves forward. 

The judge set a deadline of noon on Friday for a redacted, or blacked-out, version of the document.

The order means the public could soon get at least some additional details about what led FBI officials to search Mar-a-Lago on August 8 as part of an investigation into classified documents being retained at the Palm Beach property. 

Documents already made public as part of the investigation show that the FBI retrieved from the property 11 sets of classified documents, including information marked at the top secret level.

Search warrant affidavits typically contain vital information about an investigation, with agents spelling out why they want to search a particular property and why they believe they are likely to find evidence of a potential crime there.

In this case, though, the redactions proposed by the Justice Department are likely to be extensive given the sensitivity of the investigation and unprecedented nature of the search, lessening the chance that the public will receive a detailed glimpse of the basis for the search or the direction of the probe.

The department had earlier contested arguments by media organisations to make any portion of the affidavit public, saying the disclosure could contain private information about witnesses and about investigative tactics. 

But Reinhart, acknowledging the extraordinary public interest in the investigation, said he was disinclined to keep the entire document sealed and told federal officials to submit to him in private the redactions it wanted to make.

Even so, he acknowledged that the blacked-out portions might be so extensive as to leave the public version of the document without any meaningful information.

READ MORE: Over 100 'classified documents found' at Trump's home back in January

Unsealing facts

In his order, he said he was satisfied "that the Government has met its burden of showing that its proposed redactions are narrowly tailored to serve the Government’s legitimate interest in the integrity of the ongoing investigation and are the least onerous alternative to sealing the entire Affidavit."

After the Justice Department submitted its filing under seal on Thursday, the media coalition responded by asking the judge to unseal portions of the department's brief and to direct the government, "going forward," to file publicly a redacted version of any sealed document it submits. 

"At a minimum, any portions of the Brief that recite those facts about the investigation, without revealing additional ones not yet publicly available — in addition to any other portions that pose no threat to the investigation — should be unsealed," the news organisations wrote.

They added, "If and when additional facts come to light and are confirmed to be accurate, or certain facts no longer pose a threat to the investigation for any other reason, there is no justification for maintaining them under seal either."

READ MORE: FBI seized 'top secret' files in raid on Trump home

READ MORE: Explainer: Why is Trump facing a presidential records probe?

Source: AP