President Trump Invoked Executive Privilege. Here’s the History of That Presidential Power

When Congress issues a subpoena for documents, usually they get what they want. But that’s not the case for certain documents related to the 2020 Census question about citizenship, the Department of Justice said on Wednesday in a letter to Elijah E. Cummings, chairman of the House Oversight and Reform Committee. The reason: President Trump is invoking executive privilege.

The committee voted to recommend holding Attorney General William P. Barr and Commerce Secretary Wilbur Ross in contempt of Congress for failing to comply with the subpoenas — though the committee’s Republicans say that the administration has already provided thousands of pages of relevant documents — but Trump is unlikely to face consequences for failing to comply. That’s because the doctrine of executive privilege, which Trump invoked for the first time in his presidency just a month ago, to block House Judiciary Committee Democrats from seeing Special Counsel Robert Mueller’s un-redacted report, gives presidents wide leeway to keep secrets.

So what is executive privilege? TIME once summed up the evolution of the concept as: “George Washington invoked it, Dwight Eisenhower named it and Richard Nixon abused it.” Here’s what else to know about the term and how its use has evolved over time.

What is executive privilege?

One oft-cited definition comes from Mark Rozell, author of two books on executive privilege and the Founding Dean of the Schar School of Policy and Government at George Mason University. He defined executive privilege in a 1998 Minnesota law review article as “the right of the president and high-level executive branch officers to withhold information from Congress, the courts and ultimately the public” when it comes to “(1) certain national security needs and (2) protecting the privacy of White House deliberations when it is in the public interest to do so.”

The term “executive privilege” is not in the U.S. Constitution, but it’s considered an implied power based on the separation of powers laid out in Article II, which is meant to make sure one branch of government doesn’t become all-powerful; executive privilege is one way the legislative branch’s power over the executive is limited. For example, when Congress investigated George W. Bush’s firing of eight U.S. Attorneys in 2006, the White House Counsel at the time, Fred Fielding, alluded to executive privilege in a letter referencing the “the constitutional prerogatives of the presidency.” But prominent constitutional law expert Raoul Berger famously called it a “constitutional myth” in his 1974 book, literally entitled Executive Privilege: A Constitutional Myth.

Why do presidents need executive privilege?

The basic idea behind executive privilege is that an entity like the U.S. government requires a lot of transparency, but also can’t function if there’s no possible way to speak about things confidentially.

“All reasonably complicated organizations need some space in which people can discuss what they’re going to do, with some degree of confidentiality. Why? If you know everything you consider is going to made public, or shared in some way, then that’s going to chill your ability to have frank and open discussion,” says Michael Dorf, a constitutional law expert at Cornell Law School. “The early understanding is simply that this is just a logical consequence of separation of powers, that each branch has to be able to assert its powers relative to the other branches.”

Generally, presidents will invoke executive privilege in matters relating to national security, the military and foreign affairs, for example to protect the names of spies and informants.

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Who was the first President to invoke executive privilege?

The idea can be traced all the way back to President George Washington, who claimed it in 1792 when Congress asked him to turn over documents related to an unsuccessful military operation against Native Americans, according to Rozell’s report on the history of executive privilege for the Miller Center at the University of Virginia. Thomas Jefferson once wrote that, after conferring with his cabinet members, Washington believed “that the Executive ought to communicate such papers as the public good would permit & ought to refuse those the disclosure of which would injure the public.” Washington also claimed it when Congress requested documents related to the negotiation of the Jay Treaty with England, arguing that “the nature of foreign negotiations requires caution, and their success must often depend on secrecy.”

And Jefferson is considered the first president to establish the precedent of only releasing parts of subpoenaed material; when he was subpoenaed by his political rival Chief Justice John Marshall to present documents for the treason trial of his former Vice President Aaron Burr, who was accused of plotting to carve out the Western territories to form an independent republic, Jefferson initially refused to turn over the requested materials. The president must be able, he wrote, to “decide, independently, what papers coming to him as President, the public interest permit to be communicated, & to whom.” Jefferson eventually turned over the papers but maintained that he couldn’t be forced to do so; Burr was acquitted.

“Jefferson says that the court doesn’t have any power to issue this but I’m going to hand it over anyway because I’m a cooperative kind of guy,” says Dorf. “That set a pattern that I think we’ve seen ever since — that the President or members of an administration will cooperate to some degree, but say they’re doing so voluntarily.”

The specific phrase “executive privilege,” however, is more often said to have emerged in the 20th century. President Dwight Eisenhower invoked executive privilege more than 40 times. “Eisenhower took a very strong stand, especially during the McCarthy hearings,” Rozell told TIME in 2007. When Senator Joseph McCarthy demanded that White House officials testify in 1954 about suspected communists, “Eisenhower responded that any man who testifies to Congress about what advice he gave me will not be working for me by nightfall.”

How has executive privilege evolved?

One president who significantly changed the usage of executive privilege was Grover Cleveland, who “almost single-handedly” increased the power of the presidency in “his use of executive privilege in refusing to hand over department files to Congress in the fight over presidential appointments,” wrote Henry F. Graff, Professor Emeritus of History at Columbia University.

But Cleveland isn’t the president most people think of when they think of executive privilege. Graff goes on to say as much: “No President prior to Richard M. Nixon had ever made such an extreme assertion of executive privilege in peacetime.”

Though plenty of others have invoked the idea, Nixon remains to this day the president most closely associated with the concept. In fact, the only Supreme Court case on executive privilege is United States v. Nixon (1974), which came about when he claimed executive privilege during the Watergate investigation to get out of a grand jury subpoena and avoid handing over recordings of his conversations in the White House.

In a unanimous decision — meaning that even the conservative justices whom Nixon appointed agreed — the court ordered Nixon to hand over the tapes, arguing that presidents can’t just say that material is confidential in order to withhold criminal evidence. Here’s how TIME summarized the key points of the case in the Aug. 5, 1974, issue:

Sixteen days after this decision was handed down, Nixon resigned.

Why is executive privilege still controversial?

While the court clearly upheld the idea of executive privilege, scholars say it’s still unclear how the decision applies beyond that particular case, leaving the potential for the idea to be exploited. What is the limit to its use and how will it be enforced are questions that continue to be debated.

Many scholars worried about that problem as soon as U.S. v. Nixon was decided; because Chief Justice Burger had taken care to lay out examples of moments when executive privilege was merited (concerning “military, diplomatic, or sensitive national security secrets”) it seemed possible that future presidents merely had to invoke those ideas to hide whatever information they wanted.

Scholars say there hasn’t been enough case law to clarify whether a congressional investigation can override executive privilege. “Lower courts have tried to avoid the issue but have come down on the side of saying, ‘it’s a balancing test,’ Dorf says. “In the past, whenever possible, courts have tried to avoid making those judgments. So presidents have been very reluctant to assert executive privilege, and then the courts have tried to duck the issue, and they can. But the way things are going now, it looks not likely to be duckable — although you never know.”