Leah Millis / Reuters

After President Donald Trump appeared to exert what military lawyers call “command influence” over yet another Justice Department prosecution—this time that of his ally Roger Stone—Attorney General William Barr politely asked the president to be quiet and let him do his job. Barr got kudos across the political spectrum for standing up to the president and living to tell the tale, and still apparently basks in the president’s favor.

Of course, the more fanatical Trumpkins (those who tend to see in every disagreement further evidence of the other side’s depravity) reacted as if to the revelation of a new traitor. Their counterparts among Trump’s opponents were just as quick to slam the attorney general. Writing here in The Atlantic, Donald Ayer, who served as deputy attorney general under George H. W. Bush, called for Barr’s resignation:

The fundamental problem is that he does not believe in the central tenet of our system of government—that no person is above the law. In chilling terms, Barr’s own words make clear his long-held belief in the need for a virtually autocratic executive who is not constrained by countervailing powers within our government under the constitutional system of checks and balances.

Whatever you think of William Barr or his boss, it should come as no surprise that Barr has never said any of this. Ayer is almost certainly referring to, among other things, Barr’s strong belief in the “unitary executive.” Some critics have described this as a doctrine of autocratic power,. Yet the unitary-executive theory is quite mundane and has a respectable academic pedigree. Leading progressive legal scholars, such as the law professor and former Obama-administration official Cass Sunstein and Supreme Court Justice Elena Kagan, have deemed the theory worth contending with, and have even embraced some of its central tenets.

The unitary-executive theory holds simply that because Article II of the Constitution vests “the executive Power” in the person of the president, only the president—or those whom the president controls within the executive branch—can constitutionally exercise an “executive” federal function.

This theory has two main implications. The first is that the president must be able to control those officials who exercise executive functions at executive-branch agencies, including the rank and file of the Justice Department. This tenet enjoys widespread agreement among legal scholars, including progressive legal scholars, and has been the consistent position of the Justice Department’s Office of Legal Counsel for decades, through administrations of both parties.

Shortly after leaving the Clinton White House, where she was the deputy director of the Domestic Policy Council, future Supreme Court Justice Elena Kagan wrote a magisterial article in the Harvard Law Review. She argued that all congressional delegations of authority to executive-branch officials should be treated as delegations to the president, who should be permitted to control what those officials do with the delegated powers, in part by removing them at will.

This part of the theory is almost certainly correct, though it poses nettlesome problems for matters of federal law enforcement (such as Stone’s prosecution), to which I will return presently.

The second main implication of the unitary-executive theory is that there should be no such thing as “independent” agencies like the Federal Trade Commission and the Consumer Financial Protection Bureau, whose heads are currently shielded from removal by the president. Any agency that exercises an executive federal function, the theory holds, must be under the president’s control. In September 1985, Edwin Meese III, then the attorney general for President Ronald Reagan, gave a speech roundly condemning all independent agencies as unconstitutional. Most progressive legal scholars nowadays disagree with this—but they didn’t always.

The history of how these agencies came to be, and why they are so important now, is highly illuminating. Woodrow Wilson is rightly regarded as the father of the modern administrative state, with its plethora of independent commissions and boards. But the agencies Wilson created were not “independent” when he created them. Wilson fiercely opposed congressional interference in the internal operations of the executive branch, and he assumed, as presidents had all the way back to George Washington, that he had the power to remove the heads of any new agencies, regardless of any conditions Congress might impose.

It was a conservative Supreme Court that later made those agencies independent, an act of defiance aimed at another progressive chief executive with decidedly expansive views of executive power: Franklin D. Roosevelt.

During most of Roosevelt’s presidency, the Supreme Court was dominated by conservative judges who were adamantly opposed to the New Deal, on the grounds that it greatly exceeded the federal government’s power to regulate commerce “among the several states,” a power that had always been understood to include only those commercial transactions that actually crossed state lines. The “Scorpions,” as FDR called them, struck down virtually every one of his initiatives to impose price controls on farm products and give cartel power to labor unions—the twin pillars of the New Deal.

But in 1935, in the case of Humphrey’s Executor, the Scorpions went too far. The issue was whether a member of the Federal Trade Commission could be removed by the president at will, despite the plain language of the FTC’s enabling act, which shielded commission members from removal except for “inefficiency, neglect of duty, or malfeasance in office.”

The Supreme Court decided that because the FTC is not a purely executive agency—it is authorized by Congress to carry out “quasi-legislative” and “quasi-judicial” functions in addition to executive ones—Congress could shield its appointed members from the president’s otherwise plenary removal power. Thus we were to believe that while an agency exercising only executive functions should be controlled by the president, an agency exercising all the functions of government should be controlled by nobody. As Meese later intoned, “Federal agencies performing executive functions are themselves properly agents of the executive. They are not ‘quasi’ this or ‘independent’ that.”

After his landslide reelection in 1936, FDR felt emboldened enough by his popular mandate that he threatened to pack the Court with enough additional justices to ensure a pro–New Deal majority if the current justices did not back down. Regrettably, they did. Starting in 1937, the Supreme Court began rubber-stamping all of FDR’s initiatives. A fundamental constitutional change, which left the federal government with virtually limitless power to regulate everything under the sun, was thus secured not by the amendment process it deserved, but by the president’s naked intimidation of the Supreme Court. For many of today’s conservative legal scholars, this was a constitutional catastrophe. The framework of limited and enumerated federal powers had been replaced by a system in which the extent of federal power depended on little more than the will of transient national majorities. The rights of political minorities now likewise depended on the majority’s self-restraint, as Walter Lippmann argued in The Good Society.

This history helps illuminate why conservatives feel so strongly about strict limits on federal power, while simultaneously insisting on the unitary nature of the power vested in each of the three federal branches. The system of checks and balances, in this view, depends on a properly functioning separation of powers, and the separation of powers in turn depends on each branch being able to exercise the whole of its constitutionally vested authority. Laws should be passed by Congress, not the executive branch; enforced by the president through agencies he controls, not independent agencies; and all government actions should be subject to review by the federal courts.

This, I believe, is a fair representation of William Barr’s view of the Constitution, a mainstream view among conservative constitutional scholars. Critics may laugh and shake their heads, but the simple fact is that these people see themselves as stalwart defenders of the Constitution. Far from being a philosophy of autocratic government, conservative constitutional philosophy’s central preoccupation is precisely the prevention of autocratic government.

Many establishment Republicans who were deeply skeptical of Trump at first support him today, because, among other things, they can see that Trump’s “loose cannon” schtick is more visible on Twitter than in the day-to-day reality of the White House, which is quite humdrum, not to mention effective in achieving GOP policy objectives. And Trump has won over constitutional conservatives by elevating nearly 200 conservative judges to the federal bench, a historic achievement that could single-handedly stabilize what conservatives see as the steady disintegration of the Constitution’s very structure, as the executive branch continues its decades-long absorption of all government powers.

Barr gave a speech to the Federalist Society in November—a staunch defense of executive prerogatives—that was red meat for an audience in which the unitary-executive theory is the dominant view. Given that this view helps buttress Trump’s position, it is understandable that Republican lawyers of a Never Trump persuasion, such as Ayer and his colleagues in the Checks and Balances coalition, had a negative reaction. It is also understandable, given Trump’s criticism of the Justice Department, that many people worry that Barr is merely green-lighting what they see as the president’s willingness to use the powers of his office to go after political opponents.

But Barr and the leading conservative jurists of his generation have good reason to be so solicitous of presidential prerogatives. They lived through the presidency of Richard Nixon, who almost destroyed the legitimacy of the office itself. Congress reacted, and perhaps overreacted, by dramatically extending its oversight of—and intrusion into—executive-branch operations. Republicans who came to power after Nixon, led by President Gerald Ford, felt an urgent need to restore the legitimacy of the presidency and its prerogatives. In the midst of the Cold War, a properly functioning executive branch that could count on the public trust was a matter of national survival. And it still is.

The idea that this all comes out of a desire for unchecked presidential power couldn’t be more wrong. The entire argument between conservative and progressive jurists going back a century has consisted of conservatives trying to stop progressives from dismantling one counter-majoritarian constitutional limit after another.

That still leaves the difficult problem of who exactly should be allowed to run federal law enforcement and how to prevent that process from becoming corrupted by political influence. As is universally accepted among legal scholars the world over, the power to prosecute includes “prosecutorial discretion”—the power to decide whether and when to charge someone with a crime. And anyone familiar with the American legal system understands that the power to enforce federal law is vested in the president.

Barack Obama, for example, invented whole new ways of deploying prosecutorial discretion, discovering in it a dubious kind of lawmaking power. The goal of Obama’s executive amnesty for Dreamers may be laudable, but when he bragged, “I changed the law,” he inadvertently revealed a problem. The executive amnesty said, in effect, that the government would not prosecute certain violations of immigration law—prospectively. Leaving aside the president’s obligation to “see that the laws be faithfully executed,” this was tantamount to suspending the operation of federal immigration law with respect to whole categories of people.

Students of British history will remember that the king once had a similar power—the royal prerogative of suspension. It was eliminated by Parliament in 1689, after the Glorious Revolution, and the American Framers were careful to prevent anything like it from arising under the Constitution; hence, the power to veto a bill only upon its presentment to the president—not later, after its enactment into law. And Obama’s Dreamer orders are not the only examples. He also suspended the collection of the employer-mandate penalty under the Affordable Care Act—a statutory tax obligation. These were arguably real abuses of power, and set precedents that progressives should be thankful Trump has not availed himself of.

Trump clearly chafes at the restraints under which he has to operate, and has at times appeared slow to understand them. He appears to be in more or less constant need of senior figures such as his chief of staff, the White House counsel, and the attorney general warning him off this or that course of action. This is where his inexperience in office is most telling. Nobody who has not held federal office can imagine the minefield of legal and political hazards one has to walk through every day just to get one’s job done. But Trump does not appear to have an interest in altering the nature of the presidency or expanding executive power at the expense of Congress the way Obama did.

There is no need to impute corrupt motives to the president to see the problem that Trump’s inexperience poses for the administration of justice—particularly when you combine that inexperience with his perpetual sense of aggrieved justice. He seems to think that he has the right to say whatever he wants in his role as a celebrity as long as he doesn’t do anything inappropriate in his role as president. And Trump does routinely use—and sometimes abuse—the celebrity of his office, particularly to attack his political opponents and even members of his own administration.

What Trump may not have appreciated before the Roger Stone incident and Barr’s pushback is that his celebrity pronouncements cannot be separated from his official actions. It is one thing to joke about cancer-causing windmills knowing that it will drive the media crazy and delight the base. It is another to make public pronouncements about the prosecutorial decisions of subordinate officials, when those pronouncements cast doubt on whether the law is being faithfully executed.

Hence, Barr’s sharp reaction to Trump’s public comments on the sentencing recommendations for Roger Stone was wholly salutary. But the case is not so easily open and shut. In Trump’s mind, he is not politicizing the law-enforcement activities of the Justice Department—on the contrary, he is trying to fight the politicization of Justice Department prosecutions by his opponents within the department. And indeed some of those officials, such as Andrew McCabe, have only narrowly escaped prosecution themselves. Rank-and-file lawyers at the Justice Department are not immune to political motivations, which is why Cass Sunstein’s recent proposal to make the Justice Department independent is so problematic. Democrats soured on the idea of an independent-counsel statute after Bill Clinton’s unpleasant experience with it, and interred it once and for all. A Democratic president is no more likely to make the Justice Department an independent agency than a Republican one would be.

The president is vested with executive power. But his obligation to see that the laws be faithfully executed creates an obligation to ensure that the Justice Department is administering justice impartially. That is why the president should not interfere with ongoing investigations, as he appears to understand. It is also why he should avoid discussing ongoing investigations, as he is hopefully learning.

In the meantime, Barr faces the difficult challenge of restoring the legitimacy of the Justice Department after several years in which that legitimacy has been weakened from within and battered from without. On the right and the left, too many people have too many reasons to doubt the department’s legitimacy. In American democracy, disagreements about policy are to be expected, and can make democracy better, as long as Americans can still say they hold certain truths to be self-evident, among them that nobody is above the law, that government power must never go unchecked, and that what the Constitution says really matters.

William Barr believes that much at least, and to try to convince people otherwise is to be a bawd in way of good service.

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

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