The Justice Department officially challenged the decision to appoint a special master to assess documents recovered during the Mar-a-Lago FBI search on Friday in opposition to former President Donald Trump's request.

The DOJ has cited national security concerns and said that doing so would obstruct and delay its investigation into Trump's handling of classified documents.

The brief is the most recent step in the continuing legal battle between the DOJ and Trump.

According to a brief filed with the 11th Circuit Court of Appeals, “The uncontested record demonstrates that the search was conducted in full accordance with a judicially authorized warrant, and there has been no violation of Plaintiff’s rights—let alone a ‘callous disregard’ for them.” 

Additionally, the brief read that the “Plaintiff has failed to meet his burden in establishing any need for the seized records—indeed, a substantial number of them are not even his—or in establishing any irreparable injury in their absence.”

Even if Trump’s claims that he declassified documents were truthful, the brief further noted, then “the records could still be evidence of obstruction of justice because the grand-jury subpoena sought evidence of all records that were marked as classified.”

Trump-chosen 'special master' to serve in ex-president's legal debacle

Senior US district judge Raymond Dearie, who is experienced in handling US national security matters, was named by US District Court Judge Aileen Cannon as an independent arbiter to vet records that have been seized by the FBI upon raiding former Trump's Florida mansion. 

Cannon appointed Dearie as special master Thursday in the legal back-and-forth between Trump and the Department of Justice over the classified records found at the Mar-A-Lago resort. Dearie was one of two candidates who were suggested by Trump, with the DoJ enabling the appointment. 

The judge, furthermore, also rejected the department's demand that prosecutors be allowed to review the documents while the legal war is still in effect, rejecting also their argument that the probe into the documents is urgent due to their sensitive nature.

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