WASHINGTON — A federal appeals court on Thursday removed a major obstacle to the criminal investigation into former President Donald J. Trump’s hoarding of sensitive government documents, ending an outside review of thousands of records the FBI seized from his home and freeing the Justice Department to use them in its inquiry.
In a unanimous but unsigned 21-page ruling, a three-member panel of the US Court of Appeals for the 11th Circuit in Atlanta shut down a lawsuit brought by Mr. Trump that has hindered the inquiry into whether he illegally kept national security records at his Mar-a-Lago residence and also obstructed the government’s repeated efforts to retrieve them.
The appeals court was sharply critical of the decision in September by Judge Aileen M. Cannon, a Trump appointee, to intervene in the case. It said that Judge Cannon never had legitimate jurisdiction to order the review or bar investigators from using the files, and that there was no justification for treating Mr. Trump differently than any other target of a search warrant.
“It is indeed extraordinary for a warrant to be executed at the home of a former president — but not in a way that affects our legal analysis or otherwise gives the judicial license to interfere in an ongoing investigation,” the court wrote.
Limits on when courts can interfere with a criminal investigation “apply no matter who the government is investigating,” it added. “To create a special exception here would defy our nation’s foundational principle that our law applies ‘to all, without regard to numbers, wealth, or rank.’”
It was unclear whether Mr. Trump would appeal the decision. Lawyers for Mr. Trump did not immediately respond to a request for comment. Mr. Trump had already asked the Supreme Court to overturn an earlier decision by the appeals court that excluded 103 documents marked as classified from Judge Cannon’s review, but the justices declined to do so without any noted dissents.
More on the Trump Documents Inquiry
All three of the judges on the panel that ruled on Thursday were appointees of Republican presidents—and two of them, Andrew L. Brasher and Britt Grant, had been placed on the bench by Mr. Trump himself.
The decision came on the same day that three close aides to Mr. Trump appeared before a grand jury in Washington that is investigating Mr. Trump handling of the documents, according to two people familiar with the matter.
The aides included Dan Scavino Jr., Mr. Trump’s former social media guru, and William Russell and William B. Harrison, who worked for Mr. Trump when he was in the White House, the people said.
For more than two months, the outside review had hindered the Justice Department’s investigation into Mr. Trump’s handling of about 13,000 documents and photographs — including about 100 marked as classified — that the FBI hauled away from Mar-a-Lago in August.
That investigation is now being handled by a special prosecutor, Jack Smith, who is also overseeing a separate inquiry into Mr. Trump’s role in a variety of efforts to overturn the results of the 2020 election. A Justice Department spokesman declined to comment.
During a hearing on Nov. 22, the panel had telegraphed its deep skepticism of the legality of the unusual intervention by Judge Cannon.
In the ruling, the appeals court went through all four factors that go into determinations over whether Judge Cannon had jurisdiction and said the circumstances of the case met none of them. In particular, it noted that Judge Cannon herself agreed that the government had not shown “callous disregard” for Mr. Trump’s rights.
Under the law, the appeals court judges said, that factor was indispensable and so her finding about it alone should have ended the matter. They also said that accepting her move would set a previous that could disrupt how criminal investigations work.
“The law is clear,” the appeals court wrote. “We cannot write a rule that allows any subject of a search warrant to block government investigations after the execution of the warrant. Nor can we write a rule that allows only former presidents to do so.”
The ruling was an embarrassing development for Judge Cannon, a young jurist who found herself in the middle of a politically sensitive case.
She had not yet served two years on the bench when, in September, she shocked legal experts — and the government — by temporarily barring the Justice Department from using any of the seized materials in its investigation of Mr. Trump and installing an independent arbiter, known as a special master, to review them.
Judge Cannon’s appointment of the special master, Judge Raymond J. Dearie, was especially unusual because she gave him the power to sift through the documents not only for those protected by attorney-client privilege, which is fairly common, but also for those covered by executive privilege.
There is no precedent for a current or former president successfully invoking executive privilege to keep the Justice Department — a part of the executive branch — from viewing executive branch materials in a criminal investigation. The appeals court ruling did not reach that issue, however, since it shut down Judge Cannon’s review on jurisdictional grounds.
Shortly after her initial order came down, prosecutors asked the 11th Circuit, based in Atlanta, to reverse it and restore their ability to examine some of the most sensitive documents: a batch of about 100 that were marked as classified. The prosecutors said they needed quick and unfettered access to the classified materials to fully understand the potential hazards Mr. Trump had caused in storing them at Mar-a-Lago.
Within a week, the appeals court ruled in favor of the government, excluding the classified files from the special master’s review and restoring investigators’ access to them. In their decision, the appellate panel — which included the same two Trump-appointed judges who issued the ruling on Thursday — indicated that it thought that Judge Cannon had committed a basic error and should not have gotten involved in the case at all.
Mr. Trump appealed this early ruling to the Supreme Court, which declined to block it in a third order with no dissent. Not long after, the Justice Department returned to the 11th Circuit yet again and this time asked the court to shut down the special master’s review altogether.
The ruling on Thursday did precisely that, cutting short Judge Dearie’s work before he even had a chance to complete his review of the materials. During his brief tenure as a special master, Judge Dearie, a longtime fixture on the federal bench in Brooklyn, expressed skepticism about claims by Mr. Trump’s lawyers that the documents he was examining were in fact privileged and thus could be withheld from the Justice Department’s investigation.
In recent weeks, several witnesses connected to the that investigation have appeared in front of a grand jury in Federal District Court in Washington.