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Predictably, the lawyers for Michael Flynn, President Donald Trump’s former national security adviser, are unhappy about the refusal of U.S. District Judge Emmet G. Sullivan to immediately green-light dropping his prosecution. The Federal Rules of Criminal Procedure permit the Justice Department to withdraw the Flynn indictment only “with leave of court.” In considering such leave, Sullivan has decided to allow independent groups and legal experts to submit briefs on the issue. Presumably yet more upsetting to Flynn and his counsel, Sullivan has appointed a former federal judge, John Gleeson, to oppose the Justice Department’s request and to examine whether Flynn may have committed perjury.

In a court filing from before the Gleeson appointment, Flynn’s lawyers assert that the intervention of third parties would be unconstitutional. They write: “A criminal case is a dispute between the United States and a criminal defendant … For the Court to allow another to stand in the place of the government would be a violation of the separation of powers.”

This is constitutional nonsense. Neither the parties filing briefs, nor the retired judge advising Sullivan, are “stand[ing] in the place of the government.” They are, rather, providing information and counsel. But there is more here at stake: In monitoring the integrity of Flynn’s prosecution, Sullivan is also working to preserve the integrity of the court system he represents. In doing so, Sullivan’s effort to protect the integrity of the prosecution is an important reminder that prosecution is an executive function, but it’s a judicial one too.

The idea that federal prosecution is exclusively an executive-branch concern is not accurate. The public prosecutor was generally a far less significant government figure throughout the late 18th and most of the 19th centuries than it is today, and most definitely not seen as an inherent bearer of executive power in 1789. The British common-law tradition was one of private prosecution. Although a variety of public prosecutors appeared during the colonial period, private prosecution in the United States persisted throughout much of the 19th century. The early version of the public prosecutor in the United States was considered a judicial officer. In Joan Jacoby’s 1980 The American Prosecutor: A Search for Identity, still a leading history of American prosecutors, she explains: “At the beginning of the nineteenth century in America, the district attorney was viewed as a minor figure in the court, an adjunct to the judge. His position was primarily judicial, and perhaps only quasi-executive.”

Early state constitutions bear out the quasi-judicial character of government lawyering. These constitutions commonly authorized state legislatures to appoint certain civil officers directly or to determine by statute how officers should be appointed. The likeliest officials to be singled out this way were state fiscal officers and attorneys general. Six of the first 13 state constitutions mention an attorney general specifically, and each speaks of the attorney general in the same breath as it refers to state judges.

Nor did the first Congress do much to tie federal criminal prosecution to presidential control. The original draft of the Judiciary Act, which created the new attorney general position, would have had each federal court appoint the attorneys who appeared before them on behalf of the United States.

The first federal district attorneys—America’s original frontline federal prosecutors—were part-time functionaries, whose chief source of income was their private practice. The Judiciary Act did not provide the attorney general any supervisory power over them. The Senate rejected a request from the Washington administration to give the attorney general supervisory authority over the prosecutors, going no further than requiring district attorneys to keep the attorney general informed on lower court litigation. Although Congress, in the 1860s, finally charged the attorney general with “the general superintendence and direction” of federal lawyers, it also provided that, “in case of a vacancy in the office of … district attorney in any circuit, the judge of such circuit may fill such vacancy,” confirming once again the partly judicial character of these officials.

The authority of courts to appoint U.S. attorneys in certain cases of vacancy remains a part of federal law today. For example, the chief judge of the U.S. District Court for the Southern District of New York formally appointed Geoffrey S. Berman to the position of U.S. attorney in 2018.

Other elements of federal law bear the marks of prosecution’s judicial character. For example, it is the prosecution’s tie to the judicial function that gives rise to the absolute immunity from civil liability in tort that prosecutors enjoy in performing their prosecutorial functions. As the Second Circuit wrote in 1926: “A United States attorney, if not a judicial officer, is at least a quasi-judicial officer, of the government. He exercises important judicial functions, and is engaged in the enforcement of the law.”

Federal courts also retain explicit authority to appoint prosecutors to handle cases of criminal contempt. As a 2018 Ninth Circuit opinion explains, that authority is rooted in what has long been recognized as the “inherent power of the judiciary to appoint disinterested private attorneys as special prosecutors to pursue criminal contempt proceedings … when government prosecutors are unwilling or unable to perform that function.”

The Constitution deploys its version of the separation of powers in order to sustain the checks and balances essential to government under the rule of law. Given the Trump administration’s aggressive assertions of executive-branch authority to resist encroachments by Congress and the judiciary, it ought to recognize that the courts have their own authority to prevent other branches from corrupting the judicial function.

Among the most pernicious constitutional myths perpetuated by Attorney General William Barr, both in and out of office, are the ideas that criminal prosecution is an exclusively executive concern and that the president is constitutionally entitled to control the prosecutorial process, even when he, his family, or his close associates might be implicated. Judge Sullivan’s caution serves as a reminder that prosecution is part of the judicial function as well. His efforts to preserve the integrity of that function are not merely constitutional. They are commendable.

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

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