A federal judge's ruling this week has heightened interest in the unique role special masters play in U.S. court proceedings. It has also raised questions over the degree to which it will impact the FBI's investigation into former President Donald Trump's handling of classified documents.
Judge Aileen Cannon of the Southern District of Florida on Monday ordered the appointment of a special master to determine whether any of the documents seized from Trump's Florida home last month are privileged and should not be used by prosecutors.
Citing the need "to at least ensure the appearance of fairness and integrity," Cannon also ordered the Justice Department to stop using the seized material for "investigative purposes" while the review is conducted.
Cannon's ruling is considered a victory for Trump, who has depicted the search as politically motivated and sought to block the FBI from reviewing the documents taken during the search.
The FBI executed the August 8 search as part of an investigation into Trump's retention of presidential records, including classified government documents, after he left the White House in January 2021.
To the extent that the special master's review of the seized documents slows down the investigation, its impact remains indeterminate.
The Justice Department has already reviewed the documents taken from Mar-a-Lago. The judge's order, however, means prosecutors won't be able to make further use of the documents, such as citing them before a grand jury investigating the handling of the records.
Here are five questions about the appointment of a special master:
What is a special master?
A special master is an outside party appointed by a court to review documents and legal questions in sensitive court cases.
"You can think of a special master as 'the court's lawyer,'" said John Malcolm, a former Justice Department prosecutor.
The special master does not determine the outcome of a legal controversy such as the dispute over the Trump documents.
He or she can only make recommendations "to the judge, which the judge will consider along with arguments and counsel in order to resolve whatever the legal dispute is," said Malcolm, now the vice president of the Institute for Constitutional Government at the Heritage Foundation.
When is a special master appointed?
When investigators seize potentially privileged material from a subject's premises, the Justice Department's "filter team" conducts a review to weed out such items, typically material involving attorney-client communications.
The subject of a search can ask a judge to appoint a special master. That is what happened in the Trump case after the Justice Department turned down his initial request for a special master.
The goal is to ensure that prosecutors do not improperly view privileged records such as private emails between lawyers and their clients.
Though rare, appointing special masters in criminal cases is not unheard of, according to Jordan Strauss, a former Justice Department prosecutor, who is now a managing director at Kroll, a security consulting firm.
"Traditionally, you would see these sorts of things happen in the context of searches of attorneys' offices or review of documents from, say, an attorney who has become a cooperating witness for the government, where there is a specific concern that documents handed over by the attorney are in fact privileged," Strauss said.
In recent years, special masters were appointed in connection with searches of two former Trump lawyers, in 2018 after the FBI seized documents from Michael Cohen's office and hotel room, and in 2021 after agents took records from Rudy Giuliani's home and office.
Who will serve as the special master in the Trump case?
The judge has given the two sides — the Justice Department and Trump's lawyers — until Friday to propose a joint list of possible candidates to serve as special master.
If the parties can't agree on a candidate, Cannon has indicated that she will appoint one herself.
Often but not always, retired judges are recalled to serve as special masters. But not any judge or lawyer can fulfill the role in the Trump case. That is because more than 100 of the documents seized from Mar-a-Lago are classified, some at the highest classification level, and anyone reviewing them must have a security clearance to view secret government documents.
While Trump has claimed that he had a standing order to declassify all documents taken from the Oval Office to his White House residence, his lawyers have not made the assertion, suggesting they view the documents as classified.
To review the classified materials, Strauss said, the special master "would probably [have to] go into a secure facility and by hand, review each of the [more than] 10,000 documents and then report back to the court and potentially, eventually, the parties."
What materials will the special master be examining?
In the Trump case, the special master will be given a relatively broad mandate. Judge Cannon's order authorizes the special master "to review the seized property for personal items and documents and potentially privileged material subject to claims of attorney client and/or executive privilege."
This goes beyond what the Justice Department had wanted. Seeking to take the question of executive privilege off the table, prosecutors argued in court that only the current president, Joe Biden, can assert executive privilege claims to government documents.
Cannon, citing a 1977 Supreme Court opinion recognizing that "former presidents may assert claims of executive privilege," dismissed the argument.
"In the court's estimation, this position arguably overstates the law," Cannon wrote.
A dispute over whether Trump can assert executive privilege could lead to court battles all the way to the U.S. Supreme Court, further prolonging the investigation, according to legal experts.
"There may very well end up being legal issues related to the extent to which executive privilege remains with the former president, if at all, when the current president wishes to waive it," Malcolm said.
Is Trump receiving different treatment?
The ruling by Cannon, a Trump appointee, has drawn fire from critics who say she has acquiesced in all of the former president's demands.
Former FBI Deputy Director Andrew McCabe, now a CNN analyst, said Cannon's ruling "is very tailored to and considerate of the former president."
"There is not another litigant in the United States of America who could have gotten the same ruling," McCabe said on CNN Monday.
Conservative legal experts dismissed the criticism.
"The interpretation of some partisans will be she's a stooge of Trump, but the alternative approach is this is what she actually believes," said Saikrishna Prakash, a professor of law at the University of Virginia. "You can't decide which one it is unless you know more about this judge and most people don't know anything about this judge."