The latest sideshow stemming from Special Counsel Robert Mueller’s investigation into Russian collusion is Congressmen Devin Nunes’s (R-Calif.) and Mark Meadows’s (R-N.C.) demand for classified documents from the Department of Justice. Nunes has requested that the DOJ reveal the identity of a key source in the Russia probe, despite the DOJ’s objection that providing this information would place the source in danger. Nunes nevertheless has issued subpoenas to the DOJ and is threatening Attorney General Jeff Sessions with contempt charges and impeachment if he doesn’t comply. Meanwhile, The Washington Post has reported that Meadows plans to use a federal audit to access the DOJ memo expanding Mueller’s jurisdiction beyond his original appointment. Meadows and Nunes have grounded their aggressive requests in Congress’ constitutional oversight authority over the Executive Branch, and the Trump administration has endorsed their efforts. Though they may not realize it, in doing so they are undermining the core constitutional argument asserted by President Trump and his allies against the Russia investigation.

Trump’s emerging legal defense for obstruction of justice — floated by Harvard Professor Alan Dershowitz and others — rests on an extreme interpretation of the separation of powers known as “the unitary executive” theory. This interpretation asserts that the president has exclusive control to direct and fire anyone in the executive branch, unfettered by Congress. The unitary executive theory is based on a single clause of Article II, which states that “The executive Power shall be vested in a President.”

Trump and his lawyers have stretched this theory to an absolutist extreme. Trump tweeted , paraphrasing Joseph diGenova, “[Mueller’s] questions are an intrusion into the President’s Article 2 powers under the Constitution to fire any Executive Branch Employee…[Asking] what the President was thinking is an outrageous…..as to the President’s unfettered power to fire anyone…” Similarly, his former lawyer John Dowd argued , “[The] President cannot obstruct justice because he is the chief law enforcement officer under [the Constitution’s Article II] and has every right to express his view of any case.”

Meanwhile, when Congress has debated a bill to protected Mueller from Trump’s firing, Republican Senators have invoked a similar theory of the president’s absolute removal power to explain their votes against it. A growing number of conservatives and academics have been fighting to revive Justice Scalia’s extreme interpretation of exclusive executive control over prosecution. Some also use this theory to argue that a president can never obstruct justice by firing officials. But as Republicans in Congress assert their power over the DOJ, these academics have been conspicuously silent — maybe because Scalia was wrong, and maybe because they actually do not have a consistent position.

The text of Article II or the rest of the Constitution does not support the unitary theory. Rather, proponents of the unitary executive look to Justice Scalia’s lone dissent in Morrison v. Olson, a 1988 Supreme Court case which challenged the law giving Congress authority to appoint an Independent Counsel as a violation of the separation of powers. In Morrison, Chief Justice William Rehnquist, writing for a 7-1 majority, upheld the constitutionality of Congress’s creation of an independent counsel, selected and supervised by judges. But Justice Scalia disagreed, stating, “We should say here that the President’s constitutionally assigned duties include complete control over investigation and prosecution of violations of the law, and that the inexorable command of Article II is clear and definite: the executive power must be vested in the President of the United States.” (That’s Justice Scalia’s own original emphasis on the word “complete.”)

One of us has argued previously that Scalia was wrong on his own originalist terms. Historically, most prosecution in England and America was private prosecution until the end of the nineteenth century. The First Congress also allowed some law enforcement officials to be removable by federal judges, and it contemplated giving the Supreme Court the power to appoint the attorney general and giving district judges the power to appoint district attorneys. Many early state constitutions also reflected that prosecutors had a mixed judicial role. Scalia’s dissent was contradicted by American history.

But Scalia also overlooked Congress’s investigatory and prosecutorial powers, in some of the ways that Nunes and Meadows are illustrating now.

Congressional committees can use subpoena power to investigate crimes. And Congress has the power to enforce these powers with its own legislative contempt proceedings. Historically, Congress has internally prosecuted contempt of Congress, defined as a criminal offense .

But there is a deeper problem with Scalia’s formalistic separation. Many people don’t realize those words “separation of powers” don’t appear in the Constitution. The concept is implicit in the structure of the Constitution, but not explicit. In fact, the Framers understood the structure of the new government to be a more mixed, practical, and functional system than a strictly formal separation. James Madison’s essay titles in the Federalist Papers highlight this originalist point. For example, Federalist No.48 is titled, “These Departments Should Not Be So Far Separated as to Have No Constitutional Control Over Each Other.” And the title of Federalist No. 51 is “The Structure of the Government Must Furnish the Proper Checks and Balances Between the Different Departments.” “Checks and balances” is actually a more accurate description of Constitution’s structure.

Madison’s vision of “checks and balances” is more accurately how the Constitution works in design and practice. For example, the presidential signature or veto of legislation is a law-making legislative act. The President nominates and the Senate confirms judges. If the founders wanted complete and formal separation, judges could have been popularly elected (which is what states adopted later for greater separation and for a twist on judicial independence: separation of powers). Congress has the power to create (and repeal) lower courts, to increase or decrease the number of Supreme Court Justices, and to create “regulations” and “exceptions” for their jurisdiction. Some executive branch officials can have quasi-judicial and quasi-legislative power. (And Congress indeed can give them special job security, which gives independent agencies like the Fed an important degree of insulation from partisanship). This is a system of mixed and overlapping powers, and not strict separation.

As a result of Madison’s vision, the powers of each branch aren’t clearly defined silos but ones that overlap and sometimes clash. Nunes’s and Meadows’s current requests to DOJ seek to follow in that tradition. But if Congress can intervene in executive functions through its oversight authority, it can certainly do the same through its core legislative function, as well. Congress has the power to pass statutes criminalizing bribery or obstruction of justice. Those general laws apply to the President, just like everyone else, even when he or she uses official powers. Just as a president cannot sell pardons, the president can be guilty of obstruction if he uses pardons or removal powers to halt a lawful investigation or to shield himself or his associates from criminal liability.

Despite his earlier denunciation of Congress’ ability to criminalize his personal actions, Trump himself has acquiesced to these recent congressional efforts by tweeting his support for Nunes and Meadows: “[The DOJ lawyers] don’t want to turn over Documents to Congress. What are they afraid of? Why so much redacting? Why such unequal ‘justice?’ At some point I will have no choice but to use the powers granted to the Presidency and get involved!” And even Scalia’s supporters have remained curiously quiet in the face of members of Congress asserting their power over the executive’s criminal investigation and prosecution functions.

Even the proponents of unitary powers have now tolerated Congress’s intervention into the most sensitive details of a criminal investigation. If the supporters of the unitary executive really believe that these powers are exclusively committed to the Executive Branch, why are they now silent about such Congressional overreach? By failing to object, they are implicitly conceding that Congress does have such powers. In law, there is a concept of estoppel, a rule against making contradictory arguments. So might they be metaphorically and morally “estopped” from their wrong-headed resurrection of Scalia’s theory of extreme executive power?

Of course, the check-and-balances framework doesn’t mean that Nunes and Meadows should be able to subpoena the DOJ for whatever documents they want. This is where the difference between these two interpretations matters. Scalia framed the separation of powers with hyperformalism, with the language of exclusivity and complete control. This kind of formalism is designed to set aside practical consequences and pragmatism. Meanwhile, checks and balances is generally understood to consider practicality and functionalism. The approach of “checks and balances” rests on the balance of the overall system and the public interest, as the most important consideration.

Thus, the “checks and balances” approach tends to arrive at common sense results. Congress surely has the power of general oversight of the DOJ, and it can use the subpoena power in many cases. But those powers have limits if they interfere with or jeopardize ongoing and sensitive investigations. One lesson is that Congress has the power to give special counsels a degree of protection from presidential removal. Another take-away is that, just like Scalia’s Morrison dissent, too many of today’s originalists engage in convenient cherry-picking and selective application of principles. Scalia’s formalism fails, while functionalism makes sense of our system.

But the bottom line is that checks and balances are a better understanding of our Constitution than strict separationism, and Congress should be exercising its powers to protect the rule of law, not to undermine it.

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