U.S. District Judge James Boasberg said probable cause exists to find the Trump administration in contempt for violating his order over deportation flights last month, explaining that he didn’t reach that conclusion lightly but that officials failed to provide satisfactory answers to explain their actions.

“The Constitution does not tolerate willful disobedience of judicial orders — especially by officials of a coordinate branch who have sworn an oath to uphold it,” Boasberg wrote in a lengthy opinion Wednesday.

The judge said he would give the government the chance to remedy its contempt but if it doesn’t, he’ll proceed to identify the people in contempt and refer the matter for prosecution.

Notably, contempt is unique in that judges can appoint lawyers to prosecute it if the Justice Department declines, as one imagines could be the case if Boasberg ultimately refers any Trump officials for contempt prosecutions to the Trump DOJ. (Also notably and potentially relevant down the line, Trump-appointed Supreme Court Justices Neil Gorsuch and Brett Kavanaugh have criticized this independent appointment authority in contempt prosecutions.)

Boasberg’s ruling follows an April 3 hearing in Washington, D.C., at which he pressed the government about its compliance with his orders. Specifically, the compliance litigation centered on temporary restraining orders he issued March 15 to halt certain deportations under the Alien Enemies Act, a rarely used law that President Donald Trump invoked to summarily deport alleged Venezuelan gang members to El Salvador.

The 18th-century law had been invoked only three times before in the nation’s history, all during declared wars.

Boasberg’s ruling comes as another judge warned of possible contempt proceedings in the separate high-profile case of Kilmar Abrego Garcia, whom the government also sent to El Salvador without due process and is fighting against his return despite admitting he should not have been deported to that country.

In his opinion Wednesday, Boasberg noted that courts typically let the party in contempt “purge” (or fix) their contempt by obeying the order they violated. He said the most obvious way for the government to purge its contempt here would be “by asserting custody of the individuals who were removed in violation of the Court’s classwide TRO [temporary restraining order] so that they might avail themselves of their right to challenge their removability through a habeas proceeding.” He added that the government wouldn’t need to release any of those individuals or “transport them back to the homeland,” but he also said the government can propose other compliance methods that he would consider.

“In the event that Defendants do not choose to purge their contempt, the Court will proceed to identify the individual(s) responsible for the contumacious conduct by determining whose ‘specific act or omission’ caused the noncompliance,” the judge wrote in his opinion. He said he would begin by requiring declarations and that, if they’re unsatisfactory, he’ll proceed “either to hearings with live witness testimony under oath or to depositions conducted by Plaintiffs.”

The next step after that would be for the judge to request that the government prosecute the contempt, with him being prepared to appoint another attorney if that doesn’t happen. The relevant criminal procedural rule says: “The court must request that the contempt be prosecuted by an attorney for the government, unless the interest of justice requires the appointment of another attorney. If the government declines the request, the court must appoint another attorney to prosecute the contempt.”

Boasberg gave the government an April 23 deadline to either 1) file a declaration explaining the steps it has taken and will take to “purge” the contempt; or 2) if it chooses not to do so, to identify the people with knowledge of his order who chose “not to halt the transfer of class members out of U.S. custody on March 15 and 16.”

Trump previously called for Boasberg’s impeachment over his rulings, after which Chief Justice John Roberts issued a rare public statement that impeachment “is not an appropriate response to disagreement concerning a judicial decision.” An Obama appointee, Boasberg is the chief federal trial judge in the District of Columbia.

While contesting that they violated the judge’s orders, Trump administration officials separately asked the Supreme Court to overturn the orders. The court did so in a divided ruling on April 7, after which Trump officials argued to Boasberg that the ruling nullified any potential contempt proceedings before him. Rejecting that argument in his opinion Wednesday, Boasberg wrote that “the fact that the Supreme Court determined that this Court’s TROs suffered from a venue defect does not affect — let alone moot — the compliance inquiry presently teed up here.”

Subscribe to the Deadline: Legal Newsletter for expert analysis on the top legal stories of the week, including updates from the Supreme Court and developments in the Trump administration’s legal cases.