The Supreme Court heard oral arguments Tuesday in three cases touching on presidential immunity from congressional and grand jury investigations. If a majority of the justices side with the sweeping arguments made by Justice Department lawyers — and even more so if they are persuaded by the especially radical claims put forth by President Trump's personal attorneys — then the U.S. will have taken a big step toward elevating the presidency into a monarchical office. In this new world, the president would not only be, in effect, an elected king. He would also be a king with two bodies — more like the absolute rulers of pre-modern Europe than the head of one of three co-equal branches in a system of republican government.

The phrase "the king's two bodies" comes down to us from the political thought of the Middle Ages, and specifically from the work of the pioneering intellectual historian Ernst Kantorowicz. In his 1957 book on medieval political theology, Kantorowicz showed how thinkers in Christian Europe conceived of the political power exercised by kings. Inspired by the idea of an incarnational God and developing dualistic concepts inherited from various philosophical sources, a range of writers and artists pictured kings as having a physical, mortal body and then a second, symbolic or mystical "body politic" that endures in the monarchical office and is handed down from one corporal king to the next.

This concept helped medieval Europeans make sense of otherwise mysterious aspects of politics, such as the idea of sovereignty and its (perhaps automatic) transfer from one leader to another upon the death of a king. The theory may have been most clearly expressed in the well-known, paradoxical phrase first uttered upon the death of the French King Charles VI and the ascension of his son Charles VII in 1422: "The king is dead, long live the king!" As the centuries wore on and theories of state sovereignty became more sophisticated, the concept of the king's two bodies developed into the idea of monarchical absolutism rooted in powers inherent in the office of the king and temporarily taken on and exercised by a series of contingent individuals who hold the office.

These highly metaphysical ideas of sovereign power are very different than the concepts that animated the minds of the American constitutional framers when they devised the office of the presidency. Even those, like Alexander Hamilton, who favored a powerful executive more resembling a monarch, didn't go so far as to advocate placing the presidential office beyond the limitations of mortality and man-made law. The presidency as described in the Constitution and defended in The Federalist Papers (including those authored by Hamilton) is an office with strictly enumerated powers that are checked in a multitude of ways by the other two co-equal branches of the federal government: Congress and the judiciary.

Efforts by presidents to expand the powers of the nation's chief executive began almost immediately. John Adams supported, and Congress passed, the Alien and Sedition Acts, which gave the president the power to deport foreigners living in the country and to define and harshly prosecute treasonous activity and writing. Abraham Lincoln suspended habeas corpus during the Civil War. Woodrow Wilson both deployed censorship during World War I and advocated a much more sweeping role for the presidency within the federal government. Presidents would now use rhetoric to go over the heads of Congress and speak directly to the American electorate, attempting to shape and deploy mass public opinion with an eye to undertaking great national projects.

This vision of an active executive combined after the Second World War with the unprecedented powers of the national security state to create the leviathan of the modern presidency. In their capacity as commander in chief of armed forces stationed and countering threats (real and perceived) all around the globe, modern presidents control vast powers of surveillance, intelligence gathering, and military action. And because such powers concern matters of national security, they are often shrouded in secrecy and protected by assertions of executive privilege that have been upheld by the courts on many occasions.

That brings us to Tuesday's arguments before the Supreme Court, none of which involved anything as grave as state secrets. Instead, the three cases (Trump v. Mazars; Trump v. Deutsche Bank; and Trump v. Vance) concern Trump's business and financial dealings before and since he became president, along with those of his family. The first two cases arose from the president's effort to fight attempts by three House committees to obtain financial records (including his tax returns) to confirm that his financial and conflict-of-interest disclosures have been accurately filed. The third case follows from the president's effort to stop subpoenas from a grand jury in New York City that is looking into whether New York state laws were violated when Trump and those in his employ attempted to cover up hush-money payments.

Before the cases reached the Supreme Court, lawyers defending Trump argued before U.S. Court of Appeals for the D.C. Circuit that Congress' subpoenas are an unconstitutional attempt to harass the president. The court disagreed, upholding a ruling from U.S. District Court Judge Amit P. Mehta, who wrote that "it is simply not fathomable that a Constitution that grants Congress the power to remove a president for reasons including criminal behavior would deny Congress the power to investigate him for unlawful conduct — past or present — even without formally opening an impeachment inquiry." Douglas Letter, general counsel for the House, echoed the argument before the Supreme Court, adding that "there is nothing unprecedented about congressional subpoenas for documents that may shed light on presidential affairs."

One wouldn't think so, since the most elementary understanding of congressional oversight of the executive branch would seem to require that Congress has the power to force the chief executive to produce documents that could reveal criminal activity on his part or the part of those around him. Moreover, just 23 years ago, the Supreme Court decided unanimously in Clinton v. Jones that presidents do not have immunity from litigation in civil courts regarding acts prior to taking office. If Trump has immunity in the three cases argued on Tuesday, it would mean either that Clinton v. Jones was wrongly decided — or that presidents are shielded from investigation for criminal acts but not from investigation of non-criminal acts.

As absurd as that may sound, the latter is precisely what Trump's lawyers attempted to establish on Tuesday, arguing that Congress' attempt "to determine whether the president engaged in wrongdoing" is an unprecedented effort to harass him for political purposes and therefore "a recipe for constitutional crisis." In Trump v. Vance, the case involving the grand jury investigation in New York, the president's lawyers were even more radical, claiming that presidents enjoy a sweeping "temporary presidential immunity" that shields them from both investigation and prosecution for crimes.

This is, and should be universally judged, a preposterous suggestion, since it would quite literally permit presidents to do anything they wish, including the breaking of any law, for the duration of their term of office. But the claims of the president's lawyers in the other two cases were nearly as extreme. Congress would still be permitted to impeach presidents, but it would be deprived of the power to gather documents and investigate the need for impeachment in the first place. To call this view of presidential power expansive would be an absurd understatement. It's a vision of the presidential office conferring powers and protections on presidents enjoyed by no other American and no other officeholder. It would place presidents fully beyond the law, beyond oversight and accountability, and beyond limitations and restraints.

This is a view of the presidency barely recognizable from the text of the Constitution — and only conceivable in the very different conceptual universe of pre-modern political theory, with its vision of absolute monarchical powers conferred on those who hold the office of king. We are being asked to go along with a claim that regardless of what crimes Donald Trump (or any other potential president) may have committed before or during his time in office, and no matter how that criminality may be effecting the president's behavior or judgment in the present, he should be considered beyond the reach of investigation — because the office itself demands it and confers that uniquely absolute level of protection.

Is there any chance that the Supreme Court will be swayed by these outrageous claims? To judge by the lengthy and respectful oral arguments that took place on Tuesday, it's possible that some of the conservatives on the court will be — though Clinton v. Jones makes a presidential victory in Trump v. Vance highly unlikely. As for the other two cases, we shall see. But the fact that a president and his defenders had the audacity even to attempt the kind of arguments that they did on Tuesday — and that the nation's highest court took those arguments seriously — is an ominous sign that at least some Americans are coming to believe that the person of the president is absolutely immunized by the mystical powers of his office, placing him entirely beyond the reach of the law.

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