A federal judge has named Raymond Dearie, a senior US district judge with experience handling US national security matters, as an independent arbiter to vet records seized by the FBI from Donald Trump’s Florida estate in an ongoing criminal investigation.

Florida-based US district judge Aileen Cannon on Thursday appointed Dearie to serve as a special master in the legal fight between Trump and the Department of Justice over government documents the former president kept at his Florida resort.

Dearie was one of two candidates for the post proposed by the former president, and the US justice department had said it would not oppose his appointment.

In her order, Cannon also rejected the justice department’s demand that prosecutors would be allowed to continue their review of the seized records while the dispute is ongoing, and their assertion that the investigation is urgent due to the highly classified and sensitive material in the records.

“The court does not find it appropriate to accept the government’s conclusions on these important and disputed issues without further review by a neutral third party in an expedited and orderly fashion,” Cannon said in the ruling.

Dearie, who is 78 and based in Brooklyn, is tasked with deciding whether any of the documents seized by the FBI during the August search are privileged – either due to attorney-client confidentiality or through a legal principle called executive privilege – and should be off limits to federal investigators.

Dearie has until 30 November – after the midterms – to finish the review. Trump will be required to pay costs associated with the special master.

Earlier this month, Cannon had granted a request by Trump’s lawyers to name a special master to vet the seized records.

Trump is under investigation by the justice department for retaining government records – some of which were marked as highly classified, including “Top Secret” – at his Mar-a-Lago estate in Palm Beach after leaving office in January 2021. During a search of the property, FBI agents seized more than 11,000 records and 48 empty folders marked classified.

The justice department also is looking into possible obstruction of the investigation after it found evidence that records may have been removed or concealed from the FBI when it sent agents to the property in June to try to recover all classified documents.

Dearie served as US attorney in Brooklyn before being appointed to the federal bench there by Republican president Ronald Reagan in 1986, and was chief judge of that court from 2007 to 2011. He assumed what is called senior status – a sort of semi-retirement with a reduced case load – in 2011, a role in which he continues to serve.

The justice department had said in a court filing on Monday that Dearie’s experience as a judge qualified him for the special master role, but opposed the other candidate proposed by Trump’s team, private attorney Paul Huck. Trump’s lawyers opposed the two retired federal judges proposed by the department.

On the bench, Dearie was one of multiple judges presiding over cases against several men accused in 2009 of plotting to bomb New York City’s subway system at the direction of al-Qaida leaders.

Dearie was appointed in 2011 to the foreign intelligence surveillance court, which reviews warrant applications from the US government on matters of national security, where he served until 2019.

In 2017, he was one of four federal judges who approved warrants used to surveil former Trump campaign aide Carter Page amid concern about Trump campaign contacts with Russians, according to papers released to media outlets that sued for the records.

The justice department had opposed Trump’s request for a special master to review the seized documents to see if any should be withheld from investigators as privileged.

In ruling in favor of Trump’s request for a special master, Cannon rejected the department’s arguments that the records belong to the government and that because Trump is no longer president he cannot claim executive privilege. Cannon was appointed to the bench by Trump in 2020.

The documents probe is one of several federal and state investigations Trump is facing from his time in office and in private business as he considers another run for the presidency in 2024.