What is a special master? Court appointee to review documents Trump stored at Mar-a-Lago.

A federal judge in Florida on Monday ruled in favor of appointing a special master to review documents seized during a search of former President Donald Trump’s Mar-a-Lago estate, which yielded top secret among other classified records. 

U.S. District Judge Aileen Cannon wrote that the seizure of documents carried a stigma "in a league of its own" because of Trump’s status as a former president and that any future indictment "would result in reputational harm" to him.

Trump’s legal team requested a special master to ensure the government is not made privy to documents protected by attorney-client privilege, but the Justice Department argued that it already took steps to review the cache for privileged documents.

Here’s what you need to know about special masters and how they tie into the federal investigation of Trump.

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What is a special master?

A special master is a third-party individual – who is frequently, but not always, an attorney –  appointed by a court to oversee aspects of a case, according to Cornell University's Legal Information Institute. 

What does a special master do?

Special masters typically carry out some specific action at the court’s direction, which are "as diverse as the actions taken by courts," according to the Legal Information Institute. 

The special master appointed in Trump's case will oversee the Justice Department’s review of documents seized from Mar-a-Lago, removing any privileged material that may have been taken in the search.

Special master:Judge approves special master to review documents from Trump’s Mar-a-Lago estate, pauses DOJ probe

What are some examples of special master use?

Special masters have acted in a range of cases, from divorce and child custody cases to the aftermath of the Sept. 11, 2001, terrorist attacks. 

After the Sept. 11 attacks, Washington attorney Kenneth Feinberg was appointed as special master of the September 11 Victim Compensation Fund, where he was responsible for distributing government funds for death and injury claims related to the attacks. His work is the subject of the Netflix biopic “Worth,” in which Feinberg is played by actor Michael Keaton. 

In 1997, a judge appointed a special master in Microsoft v. United States to advise the court on technical issues and investigate claims, like Microsoft’s suggestion that Windows would be made slower if Internet Explorer were to be removed, according to the Legal Information Institute. 

In a case similar to Trump’s, a special master was appointed to oversee the document review in the federal investigation of the ex-president’s former lawyer, Michael Cohen. Cohen’s legal team argued at the time that a special master appointment was necessary to ensure documents covered by attorney-client privilege weren’t reviewed by the government. They also claimed a special master appointment would “protect the integrity of the Government’s investigation from the toxic partisan politics of the day.”

Special masters also often appear in original jurisdiction cases, frequently involving boundary disputes between states, decided by the Supreme Court, according to the Legal Information Institute. 

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Why does Trump want a special master? 

Trump’s legal team filed a lawsuit in August seeking to halt the continued review of classified documents taken from his Mar-a-Lago property until a special master could be appointed to ensure possibly privileged material is shielded from scrutiny. 

In the filing, the former president’s lawyers argued that the search was both political and overly broad because it authorized FBI agents to seize "boxes of documents merely because they are physically found together with other items purportedly within the scope of the warrant."

What was the DOJ's stance?

The Justice Department claimed that the appointment of a special master would impede the government’s investigation, which it says has already uncovered evidence of obstruction in the handling of classified records. 

The agency also said that federal authorities had already assigned a “privilege review team” to sort and exclude material that may not be relevant or information that may be privileged, noting that authorities had already identified a “limited set of materials” that may contain information protected by attorney-client privilege.

DOJ's perspective:DOJ says it’s ‘likely’ Mar-a-Lago documents were hidden and efforts made to obstruct probe

What impact does the judge's ruling have on the DOJ's investigation? 

In the same ruling approving the designation of a special master, U.S. District Judge Aileen Cannon called for a temporary halt to the federal inquiry until a document review is completed.

The Florida judge asked Trump's team and the government to submit potential candidates for the special master role by Friday.

What will happen next?

The Justice Department told USA TOAY that it was reviewing the decision.

"The United States is examining the opinion and will consider appropriate next steps in the ongoing litigation," department spokesman Anthony Coley said.

Contributing: Kevin Johnson, Bart Jansen