With special counsel Robert Mueller and other federal prosecutors appearing to narrow in on President Donald Trump himself in recent weeks, concerns have been raised about the potential for presidential interference with Mueller and his investigation into the 2016 presidential election campaign. Republican Sen. Jeff Flake of Arizona has refused to advance Trump’s judicial nominees as long as a bill to protect the special counsel is held up in the Senate, while Democrats have again sounded the alarm over the potential that Trump might fire Mueller. The pending attorney general nomination of William P. Barr, an aggressive defender of executive power, to again head the Justice Department does nothing to ease that nervousness.

Mueller’s fate aside, one of the most critical tools in the special counsel investigation has been the Washington, D.C. federal grand jury empaneled by Judge Beryl Howell in 2017. Commentators have divided on the question of whether the grand jury could proceed on its own without Mueller’s participation should he be dismissed. However, analysts who have answered this question both affirmatively and negatively have generally not analyzed an important, though perhaps unprecedented option: Howell should have the power to appoint a new prosecutor should Mueller be fired and the Justice Department not replace him with someone to lead its investigation to conclusion.

Despite the common perception that grand juries are prosecutorial tools, they are not part of the executive branch. The Supreme Court has said that “the whole theory of its function is that it belongs to no branch of the institutional government, serving as a kind of buffer or referee between the Government and the people.” The fact remains, however, that grand juries are constituted by courts, not by the Justice Department, and they have ancient historical ties to the judiciary. Further, although the supervisory powers of the empaneling judge are limited, grand juries depend on court subpoenas to compel the appearance of witnesses and the production of material evidence. It is the court that will sanction a witness for contempt if he or she disobeys a subpoena without adequate excuse, not the prosecutor.

It’s worth considering the closest historical parallel when reviewing options for Howell to keep the grand jury going even in the aftermath of hypothetical presidential interference. After Richard Nixon ordered the dismissal of Archibald Cox as the Watergate special prosecutor, Judge John J. Sirica, who had convened two Watergate-related grand juries, contemplated just such a course. As the Washington Post’s David Ignatius recalled in a column last April, Sirica wrote in his memoir, To Set the Record Straight: The Break-in, the Tapes, the Conspirators, the Pardon, that his “first concern [after Cox’s firing] was that the grand juries be protected.” Three days after the “Saturday Night Massacre,” he assured the grand jurors: “These two grand juries will continue to function and pursue their work. … You must steadily and deliberately pursue your investigations.”

So what would happen if, say, Mueller were dismissed and the Justice Department failed to volunteer another prosecutor to assist the grand jury? Although there may not be a clear answer, it is certainly conceivable that the grand jury might turn to Howell and formally ask her to request the Justice Department to provide a successor. If the Justice Department declined, it is plausible that Howell would have inherent judicial authority to appoint private counsel to perform that role.

How might that work? The Constitution expressly authorizes the appointment of “inferior officers” by courts of law. For example, federal law currently allows the attorney general to appoint an acting U.S. attorney for 120 days in any judicial district where a vacancy occurs. But if 120 days pass without the appointment of a duly nominated and confirmed successor, “the district court for such district may appoint a United States attorney to serve until the vacancy is filled.”

There is no doubt that, in granting a grand jury request for a prosecutorial appointment, Judge Howell would be breaking new ground.

Further, the judiciary has inherent power to appoint prosecutors to defend the autonomy and integrity of the judiciary. Under the Federal Rules of Criminal Procedure, a court that thinks itself the target of criminal contempt “must request that the contempt be prosecuted by an attorney for the government, unless the interest of justice requires the appointment of another attorney.” But “[i]f the government declines the request, the court must appoint another attorney to prosecute the contempt.” As the 9th Circuit has recently observed, “Rule 42 is rooted in the longstanding inherent power of the judiciary to appoint disinterested private attorneys as special prosecutors to pursue criminal contempt proceedings in federal court when government prosecutors are unwilling or unable to perform that function.” In other words, a court need not depend on a recalcitrant executive branch when self-help is necessary to vindicate a court’s judicial powers.

The grand jury’s work may be of constitutional dimension, even if it does not culminate directly in a criminal indictment of the president. Leon Jaworski, Cox’s successor as Watergate special prosecutor, doubted his authority to indict Nixon for obstruction of justice. Yet he led a grand jury to approve a report, only recently unsealed after being stored behind closed doors for decades at the National Archive, that has come to be known as the Watergate “Road Map.”

Unlike the controversial Starr report regarding Bill Clinton, the Road Map steered away from recommendations or legal conclusions. It instead just recited the grand jury’s key findings of fact, each statement linked by annotation to its substantiating evidence. On behalf of the grand jury, Jaworski sought and obtained Sirica’s approval to transmit the document to the House Judiciary Committee. And importantly, in granting the transmittal request, Sirica affirmed his court’s authority to determine both the report’s propriety and its limited disclosure. The evidence quite likely proved critical to the committee’s determination to impeach Nixon for obstruction of justice.

There is no doubt that, in granting a grand jury request for a prosecutorial appointment, Howell would be breaking new ground. And a Barr Justice Department, instead of refusing to appoint a successor special counsel, might instead select a prosecutor to “assist” the grand jury by cutting off its investigation and refusing to compile its findings. That could confront Judge Howell with yet another conundrum: Should the grand jury resist and seek to complete its report, she would have to decide how far to go in preserving its independence. This would no doubt require careful inquiry into the traditional authorities of the grand jury and the separation-of-power implications of allowing the jury to circumvent its assigned prosecutor and provide a Russiagate Road Map.

Uncertainty as to the future of the Russia investigation will surely not abate amid the president’s Twitter storms. But as Americans contemplate the ways in which the Trump administration has blasted through norms essential to democracy and the rule of law—and the prospect of more to come—it is worth considering that we might have in place a constitutional framework that allows the courts to play a checking-and-balancing role that will allow the facts to come to light.