Loren Elliott / Reuters

Perhaps nothing can persuade Republican senators to convict President Donald Trump, but on Friday, as Representative Zoe Lofgren deftly explained why Trump’s blanket defiance of every House subpoena and request for witnesses was an impeachable obstruction of Congress, the mood in the room noticeably shifted. I had the good fortune to be sitting in the Senate gallery to witness this myself. Republican senators whose attention had wandered refocused one by one until—unusually for this trial—the entire Senate was listening intently to an argument and seemed to be considering it seriously.

The reason for the sudden attentiveness is not far to seek. Representative Lofgren was telling senators of both parties that Trump’s response to the House investigations that led to his impeachment was not merely a middle finger raised to Democrats, but an affront to Congress as a whole. She made clear that, left unrebuked, Trump’s defiance will gut the constitutional authority of both House and Senate not merely to check the personal excesses of any given president, but to oversee the entire executive branch. In short, Lofgren was forcefully reminding Republican senators that Trump is a threat to their own legitimate constitutional power.

On Saturday, Trump’s lawyer Pat Philbin tried to extinguish any flickers of enlightened self-interest among Republicans by arguing that Trump was entitled to stonewall the House because the House hadn’t properly authorized its own subpoenas. Like so many contentions of the president’s defenders, this is malarkey thinly draped with plausible-sounding distortions of facts, rules, court opinions, and the Constitution itself.

Let’s begin with the Constitution. Article I grants Congress an array of powers, primarily the power to legislate.* But it’s easy to forget that the predominant subject of legislation is the executive branch. In our era, there is a tendency to think of the entire executive branch—the military, the innumerable civilian departments, agencies, commissions, and boards—as a kind of organic extension of the person of the president. But under the Constitution, every single component of the executive branch other than the president himself exists only because Congress once passed a statute saying that it should, and thereafter enacted annual appropriations to provide for its continuance. Moreover, most of what the 2 million or so federal employees who staff the executive do every day is dictated by a congressional statute or a regulation promulgated pursuant to such a statute.

Therefore, under the Constitution, Congress has both a responsibility and a right to inquire closely into the operations of the federal agencies, programs, and employees it authorizes, regulates, and funds. The power of inquiry includes the power to use subpoenas to compel production of testimony and documents. The Supreme Court has repeatedly recognized this “oversight power” and held it to be “coextensive with the power to legislate.”

Courts have held that a legislative demand for information under the oversight power must relate to a “valid legislative purpose.” But the only instances when congressional subpoenas have been held out of bounds for not relating to such a purpose involved demands for information about private persons. The Supreme Court has never found a congressional inquiry into the operations of the government itself or the behavior of government employees in their official capacities to lack a valid legislative purpose.

In addition to the oversight power implied by its legislative authority, Congress possesses enhanced constitutional authority under the impeachment clauses to inquire into the conduct of the president and other impeachable “civil officers.” The “sole power of impeachment” granted to the House of Representatives by Article II, Section 3, would be meaningless if the House could not compel production of the evidence necessary to determine whether impeachable conduct had occurred.

It is crucial to understand that the general oversight power and the specific impeachment-investigation power are not mutually exclusive. In other words, if Congress is concerned that a president is acting contrary to law or misbehaving in his direction of agencies of the executive branch, that is a proper subject of its oversight authority. Inquiring into the conduct of the executive branch, including its constitutional head, is the purpose of the oversight power. The fact that the president’s behavior in a particular matter might become grounds for impeachment doesn’t exempt that matter from ordinary oversight.

With this constitutional background in mind, consider the sequence of events that led to Trump’s impeachment.

On August 28, 2019, Politico reported that aid to Ukraine previously authorized by Congress was being withheld by the Trump administration. Within a week, The Washington Post reported that the hold might have been placed to induce Ukraine to investigate Joe Biden and his son Hunter. This was obviously a matter of legitimate legislative concern because it related both to the proper expenditure of particular congressionally appropriated funds and to more general issues of the conduct of American foreign policy and election integrity. Not to mention it also implicated the president’s own conduct.

Accordingly, on September 9, three standing House committees—Foreign Affairs, Intelligence, and Oversight—announced investigations into the blocked aid. Two days later, on September 11, the White House released the hold. Over the ensuing weeks, the committees issued a series of subpoenas to the administration for testimony and records. The administration complied with none of them, and on October 8, White House Counsel Pat Cipollone sent Speaker Nancy Pelosi a letter declaring a policy of total noncooperation with House investigations.

The president has maintained that policy since. At least 12 administration witnesses sought by the House have declined to appear, on White House instructions. Some current and former government employees have testified in compliance with subpoenas, but all of them did so contrary to White House directives. The House subpoenaed more than 70 categories of documents from executive-branch agencies, including the Departments of State, Defense, and Energy, and the Office of Management and Budget, and received exactly zero documents in return.

This categorical refusal is without precedent or legal justification. Past presidents have certainly resisted production of specific testimony or particular documents. But even then, they have done so by invoking judicially recognized doctrines such as executive privilege (which applies only to communications with the president’s closest advisers and must yield to a showing of need). No recognized privilege authorizes government-wide noncompliance with Congress. No president has ever presumed to order the entire executive branch to refuse to respond to congressional subpoenas, whether issued pursuant to oversight power or as part of a specifically designated impeachment investigation.

This would seem to make the case for obstruction under Article II ironclad. But the president’s lawyers have seized on a peculiarity of the House process in this case.

Although the House investigation into Ukraine was initiated by three standing committees exercising their general oversight power and the subpoena power conferred on them by Rule X of the standing rules of the House, on September 24, Speaker Pelosi announced her support for an impeachment inquiry. But not until October 31 did the House as a whole approve a resolution formally declaring the ongoing investigations to be an impeachment inquiry and laying out the process for its public phase.

The president’s counsel argues that all the subpoenas issued by the Foreign Affairs, Intelligence, and Oversight Committees prior to October 31 were invalid because the House hadn’t formally adopted an impeachment resolution. Therefore, they say, the president had no obligation to comply with any of them, thus exonerating him from obstruction. That is, to be plain, ridiculous. The three House committees that began the investigation on September 9 indisputably had the constitutional authority to do so as part of the oversight power. And they had the express authorization to issue subpoenas under House rules. The president’s position, incredibly, is that if an ongoing oversight investigation begins to produce evidence that might result in impeachment, the committees conducting that investigation somehow lose their subpoena authority until the whole House declares a formal impeachment inquiry.

This is, not to put too fine a point on it, absolutely daft. The power of the House to compel presidential disclosure increases once impeachment is contemplated. Some have argued that this increment of constitutional authority is not available unless and until the House formally declares that it is engaging in an impeachment inquiry, a point I have refuted elsewhere. But the White House is now arguing that the ordinary investigative powers of Congress disappear as soon as it becomes evident to House leadership that impeachment should be contemplated.

Not only is this view unfounded in the Constitution, but it would create an absurd catch-22. It is certainly right that the House should not convene a formal impeachment inquiry unless there is substantial evidence upon which to premise so grave a step. But except in a case where the matter at issue has already been investigated by the Senate or outside agencies (as was true with Richard Nixon and Bill Clinton), the only way to get such information is for the House to demand it under its general oversight authority. Trump is saying that, with respect to any subject on which the House might find the president impeachable, he can issue a blanket order to the entire executive branch blocking access to information unless and until the House passes a formal impeachment-inquiry resolution. As long as he can enforce compliance with that order, the House will not get such information … and the result is checkmate.

And even when, as proved to be true here, patriotic, law-abiding executive-branch officials defy his directive and come forward, as long as important witnesses comply with his orders and the entire bureaucracy refuses to produce necessary documentary evidence, he can defend against impeachment based on a “lack of evidence.”

If the Senate, or its Republican members, accept the devious justification for defiance of Congress offered by Trump’s lawyers, they will validate a strategy of complete obstruction of congressional inquiries by this and future presidents. The result is not only to neuter the impeachment power, but more profoundly, to cripple the fundamental check on executive mismanagement, abuse, corruption, and overreach embodied in their own power of oversight.


*This article previously misstated where in the Constitution the powers of Congress are granted.

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

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