A judge in the United States has ordered the Department of Justice to publicly release a redacted version of an affidavit that underpinned the FBI’s search of former President Donald Trump’s Florida home earlier this month.

US Magistrate Judge Bruce Reinhart ordered the redacted document’s release by noon (16:00 GMT) on Friday.

Reinhart’s order on Thursday came just hours after a Justice Department spokesman confirmed that prosecutors had submitted a sealed copy of its affidavit with proposed redactions to the judge. Those redactions are likely to be extensive, so it is unclear how much new information about the investigation will be revealed.

Reinhart said the Justice Department had valid reasons to keep some of the document secret, including the need to protect the identities of witnesses and federal agents, as well as the government’s investigation and strategy and grand jury material.

“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,” he wrote in Thursday’s order.

The affidavit – a sworn statement outlining the evidence that gave the Justice Department probable cause to seek a search warrant – is likely to contain key information about the FBI’s reasoning for the raid at Trump’s Mar-a-Lago estate on August 8.

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

Reporting from Washington, Al Jazeera’s Mike Hanna said while “it’s likely that any names of witnesses or FBI agents will be redacted” from the affidavit, it remains “an incredibly important document”.

“It will give an insight into the timeline of events leading to that unprecedented search of the former president’s home,” Hanna said.

Several news organisations had asked the court to make the affidavit public, arguing its contents constitute a matter of “utmost public interest”.

The media coalition responded to Thursday’s filing 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.

The groups noted that significant information about the investigation is already public. “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.”

But the US government has argued that releasing the affidavit would compromise its ongoing probe, revealing information about witnesses and potential next steps to be taken by investigators and prosecutors.

The Department of Justice is investigating violations of three laws, including a provision in the Espionage Act that prohibits the possession of national defence information and another statute that makes it a crime to knowingly destroy, conceal or falsify records with the intent to obstruct an investigation.

Trump and his supporters have claimed the search was politically motivated, and a recent Reuters/Ipsos poll found that 54 percent of Republican voters said they believed federal law enforcement officials behaved irresponsibly in the case.

The former president on social media called for the affidavit to be unsealed, though his lawyers had not weighed in on the matter.

Claire Finkelstein, a law professor and academic director of the Center for Ethics and the Rule of Law at the University of Pennsylvania, told Al Jazeera last week that two main types of material, in particular, will need to be redacted should any part of the affidavit be made public.

That is, anything that touches on highly sensitive, national security issues – nuclear secrets, for example – and anything that pertains to grand jury secrecy. “The amount of information that could be left after those redactions may be very, very limited,” Finkelstein said.

On Monday, lawyers for Trump sought to prevent the FBI from continuing to review documents recovered during the search at Mar-a-Lago until a neutral “special master” is appointed to inspect the records.

The motion, filed in federal court in West Palm Beach, Florida, also asked investigators to return any items outside the scope of the search warrant. “Politics cannot be allowed to impact the administration of justice,” the filing stated, adding: “Law enforcement is a shield that protects Americans. It cannot be used as a weapon for political purposes.”

US District Judge Aileen Cannon has asked Trump’s legal team to file a more targeted request by Friday that better explains what relief the former president is seeking and why his request should not be sent instead to Reinhart. (Al Jazeera)

•PHOTO: Former US President Donald Trump on social media called for the affidavit to be unsealed, though his lawyers had not weighed in on the matter [File: Erin Siegal McIntyre/Reuters]

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