Tom Brenner / Reuters

The House has now begun the public phase of its impeachment process. But during its closed-door sessions last week, more than 10 current and former executive-branch officials—including Acting Chief of Staff Mick Mulvaney and the top National Security Council lawyer, John Eisenberg—refused to show up. Each had been subpoenaed to appear. Compliance with a subpoena is not normally optional, of course.

But the witnesses declined to appear, at the White House’s direction. The White House argued that the Constitution’s separation of powers prohibits Congress from requiring close presidential advisers, such as Mulvaney and Eisenberg, to testify, and prohibits Congress from requiring any executive-branch official to appear for a deposition without a government lawyer present, two “prophylactic” constitutional doctrines—one old and one new—that the executive branch says are necessary to protect executive privilege. These doctrines purport to allow current and former executive-branch officials to refuse to comply with a congressional subpoena. But they have never before been applied to a formal impeachment inquiry. Nor has executive privilege.

When the Democrats reclaimed the House of Representatives in the 2018 election, a common refrain was that the terrain in Washington had shifted. The Democrats would now have the constitutional authority to conduct oversight of the Trump administration, including by issuing subpoenas to demand particular documents or to require witnesses to testify. Understanding that shift, Donald Trump said he was ready to adopt a “warlike posture” in response.

The warlike posture, or at least posturing, did not take long to emerge. In April, Trump announced that his administration would “fight all the subpoenas.” And, amid a flurry of oversight on various matters, the administration responded aggressively to information requests and suggested it would not comply. But behind the posturing, the letters sent from executive-branch agencies and the White House to congressional committees sounded very similar to letters sent during the Obama administration to Republican-controlled House committees and, before that, during the George W. Bush administration to Democratic-controlled House committees. In the past, after the bluster and posturing came compromise, at least in the large majority of disputes. This time, however, neither side intended to back down.

What the ensuing months have demonstrated is that the executive branch can rely on executive privilege, along with a constellation of doctrines arising out of it, to render congressional oversight virtually impotent, at least as long as officials are willing to follow the White House’s direction not to appear. The roots of the executive branch’s constitutional theories are long-standing and, in many instances, bipartisan. The administration’s claim that former White House Counsel Don McGahn is absolutely immune from compelled testimony, for example, garners almost all its support from a 2014 opinion issued by the Department of Justice’s Office of Legal Counsel (OLC) during the Obama administration.

As the clashes between the two branches have escalated, however, the Trump administration has expanded these existing doctrines to stake out aggressive new positions about executive privilege, immunity, and the limits of Congress’s oversight authority. And the administration has developed new prophylactic rules that it argues are constitutionally required to protect executive privilege, including that a witness subpoenaed to appear for a deposition need not comply with the subpoena if a government lawyer is not permitted to attend.

But the House has now formally authorized an impeachment inquiry.  Impeachment and oversight are distinct constitutional authorities belonging to Congress, and there is good reason to think that impeachment, unlike everyday oversight, fundamentally alters the balance of power between the two branches. As Raoul Berger, the conservative legal historian and scholar, wrote in 1974, the impeachment power “constitutes a deliberate breach in the doctrine of separation of powers, so that no arguments drawn from that doctrine (such as executive privilege) may apply to the preliminary inquiry by the House or the subsequent trial by the Senate.”

OLC issued a letter opinion on November 1 arguing, in essence, that impeachment does not change anything. And in a subsequent letter supporting Eisenberg’s immunity, it claimed that “the commencement of an impeachment inquiry only heightens the need to safeguard the separation of powers.” OLC’s letter opinion reasoned that the House of Representatives is akin to a grand jury when it exercises its constitutional impeachment authority, and that courts have applied executive privilege to demands for information from grand juries. It relied on the foundational Supreme Court decision on executive privilege—United States v. Nixon—which involved a grand-jury subpoena to President Richard Nixon for the Watergate tapes. Although the Court held that the tapes did enjoy a presumptive privilege, it ultimately concluded that the privilege was overcome by the grand jury’s need for them.

But, as some advocates have been known to remark about Supreme Court briefs, the “bodies”—that is, the unfavorable precedents or issues the author wants to gloss over—are buried in the footnotes. In the five-page letter opinion, the “body” is the entire historical understanding of executive privilege in the context of impeachment. And that history is buried and dismissed in the first footnote. There, the opinion quotes a prior OLC memorandum on impeachment stating that “precedents relating to the subject of executive privilege in presidential impeachment are meager, confused and inconclusive.” But, unlike a traditional OLC opinion, the letter opinion omits any direct discussion or analysis of the wealth of historical information and presidential statements about the application of executive privilege to impeachment.

What’s the right answer, then?  May the president assert executive privilege to withhold information during an impeachment inquiry? The answer, as a historical matter, is almost certainly no. (This conclusion and others in this essay are solely my personal views and are not made in my official capacity as Assistant Solicitor General for Tennessee.) The authority of the House to demand information as part of an impeachment inquiry arises out of the Constitution’s declaration that the House shall have the “sole power of impeachment.” And that constitutional authority derives directly from the authority of the House of Commons in the English Parliament. James Wilson, one of the principal architects of the Constitution, described the House of Commons as having the “character of grand inquisitors of the realm.” He recognized that “the proudest ministers of the proudest monarchs have trembled” at a censure from the House of Commons, and “have appeared at the bar of the house to give an account of their conduct, and ask pardon for their faults.”

For that reason, George Washington and his advisers agreed that the president’s authority to withhold documents from the House would not apply to impeachment. In one instance, the House had requested information relating to the controversial Jay Treaty, which had led some to call for Washington’s impeachment. Washington and his advisers concluded that the president had the constitutional authority to withhold the documents unless the House opened a formal impeachment inquiry. And a number of other presidents who have asserted their constitutional authority to withhold documents from Congress at times have also recognized that an impeachment inquiry would be different. President James K. Polk probably stated it most clearly, opining that in the exercise of the impeachment power, the House could “penetrate into the most secret recesses of the Executive Departments … command the attendance of any and every agent of the Government, and compel them to produce all papers, public or private, official or unofficial.” And President Theodore Roosevelt once ordered an official to turn over to him all the papers demanded by Congress, and then informed a senator that “the only way the Senate or the committee can get those papers now is through my impeachment.”

Two other past statements bear particular mention. Attorney General Robert Jackson’s memorandum on the confidentiality of law-enforcement files remains the seminal document on which the executive branch relies to withhold such information from Congress. But at the end of the analysis, Jackson noted, “Where the public interest has seemed to justify it, information as to particular situations has been supplied to congressional committees.” And he then identified one such situation: “Pertinent information would be supplied in impeachment proceedings … for the good of the administration of justice.”

Nixon, not one to cede executive authority lightly, argued through his personal counsel that he did not have to provide information subpoenaed by a Senate committee. But he acknowledged that a request from the House in an impeachment inquiry would be different. He reasoned that the president “is answerable in only one constitutional proceeding . . . the deliberate action of the whole Congress under the Impeachment Clause.”  And although he initially suggested he may attempt to assert executive privilege in the Watergate investigation, before impeachment proceedings had begun, he eventually recognized it was not available.

Given this history, how can executive-branch officials repeatedly refuse to testify in the impeachment inquiry? The immediate answer is straightforward: They have not relied on executive privilege. Instead, they have relied on testimonial immunity or refused to appear because government counsel would not be allowed to attend.

But the straightforward answer is misleading. The reason OLC originally concluded that an official could refuse to comply with a deposition subpoena if government counsel were not allowed was because the exclusion of government counsel would unconstitutionally interfere with executive privilege. And the origin of immunity lies in the fact that almost all the information the presidential adviser would testify to would be presumptively privileged. The recalcitrant witnesses have not asserted executive privilege. But ultimately, executive privilege is the foundation of their constitutional argument that they can refuse to comply with the congressional subpoenas.

If executive privilege does not apply to impeachment, that foundation crumbles. And the prophylactic defenses crumble along with it. The November 1 letter opinion attempts to shore up that foundation to prevent that from happening, at least until a court says otherwise. But the fundamental problem with the opinion is that it never addresses the truly pertinent question. It concludes that executive privilege applies, and can be overcome only by some undetermined showing of congressional need. And, it reasons, because the privilege theoretically could apply, then the rule that government counsel must be allowed in a deposition applies as well.

What is missing is the most relevant logical step: whether executive privilege would be overcome by Congress’s need for information in a formal impeachment inquiry. And the fact is, it almost certainly would. Almost every president who has addressed the question, not to mention scholars and other executive-branch officials, has concluded that executive privilege, even if theoretically applicable to impeachment, would almost always be outweighed by Congress’s need to conduct a comprehensive inquiry, in the same way it was outweighed in Nixon by the grand jury’s need for the Watergate tapes. The analogy to Nixon at the heart of the OLC letter opinion thus highlights the opinion’s fundamental error and omission: the necessity of balancing interests.

The administration is currently asserting not only that qualified executive privilege applies to impeachment, but that the privilege remains so important, even in impeachment, that it warrants absolute protection. On that basis, more than 10 witnesses have refused to testify. And more will likely do the same if the House or Senate continues to issue subpoenas and officials continue to follow the White House’s direction. Ultimately, the president may not need to assert executive privilege at all. These absolute, prophylactic doctrines such as immunity and the deposition-counsel rule do not just protect executive privilege; they ultimately protect the president from ever having to undertake the balancing of public interests that has historically been at the core of executive privilege and that the Supreme Court found to compel disclosure in Nixon.

Lucky for him. Otherwise, he would be faced with either providing the information sought or contradicting a long history of presidents and other executive-branch officials who have concluded that the public interest requires full disclosure from the president during an impeachment investigation.

This story is part of the project “The Battle for the Constitution,” in partnership with the National Constitution Center.

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