On Thursday, Judge Dana Sabraw held what could be the most consequential hearing in months in the family separation case Ms. L v. ICE, which has resulted in the identification and reunification of more than 2,000 separated children with their parents. The new developments could lead to the identification of thousands more separated children, or a bitter court fight over whether the Trump administration has the responsibility to account for them.

An inspector general’s report last month revealed that potentially thousands more children were separated from their families than previously acknowledged by the government. The American Civil Liberties Union, which is leading the lawsuit, quickly asked for the government to identify those separated children for possible reunification. The court’s initial reunification order has been applied only to children who were in Office of Refugee Resettlement care at the time Sabraw’s preliminary injunction was sent down on June 26. The government filed a response to the ACLU’s motion saying that it would be too difficult to find the additional kids it separated and that reunification would be potentially traumatic because it would involve Immigration and Customs Enforcement raiding homes where these children have been placed.

The government seems to have dropped that latest argument, acceding to the fact that reuniting children could be done—as it has been throughout the course of the lawsuit—with the help of nongovernmental organizations.

Lawyers for the Department of Justice, though, continued on Thursday to press their case that the government does not have an obligation to identify those families and that the task would be too onerous. They even seemed to indicate that, should Sabraw find a government obligation to account for all illegally separated children, as he seemed inclined to do, they would drop their previous cooperation and fight the ruling.

“It’s a real change of course, respectfully your honor, to do all that [work to reunite families], to put all that commitment in, to hold a potential appeal in abeyance, to grant all sorts of things that we wouldn’t normally grant,” said Deputy Assistant Attorney General Scott Stewart. “I’m just not sure that we can keep going that way.”

During Thursday’s hearing, Sabraw seemed poised to accept the ACLU’s motion. As the ACLU argued in its filings in the case, the government’s position is illogical. The DOJ argues that the government only has a responsibility to identify separated children who were in ORR custody on the date of Sabraw’s court ruling, June 26, because the remedy the court ordered—reunification—would present different challenges for the other group. The ACLU argued in its own filings that “this confuses the question of relief with the question of liability. The pre-June 26 children suffered the same harm from the same illegal government policy.”

The judge seemed to echo this position throughout Thursday’s proceeding. “The alleged wrong was the government conduct of separating the families as a matter of policy,” Sabraw said. “That class, as the plaintiffs would like [the court] to find it, seems to me would logically start with this policy, which was initially implemented … that could go back to July of 2017.”

While family separation came into the national consciousness last summer after it was implemented across the Southern border, the IG report found that a “pilot” version of the program had been running in the El Paso, Texas, sector as far back as July 2017.

“Shouldn’t the class include everyone who has been allegedly unlawfully separated?” Sabraw asked the government. “Why would it be tethered to an arbitrary date?”

“Isn’t it important to the process to have an accounting?” the judge continued. “Simply to have an accounting of what happened to whom, how many were involved, and where are they?”

Stewart argued that an accounting wasn’t proper because the missing children in question hadn’t been identified by the ACLU and that “this is something that arose only very, very recently.”

As Sabraw noted, classes are updated all the time when new information is revealed, as in this case. “When the preliminary injunction was issued in June of 2018, at that time there was information that was not known to the court, the government counsel, and to plaintiff’s counsel, it would appear,” he said. “Viewed in that light, the June 26 date becomes very arbitrary,” he added.

The ACLU’s lead attorney, Lee Gelernt, told Slate that the government’s position was essentially: “We cleaned up half the mess, we don’t have to clean up all the mess.”

Again, the judge seemed to view the date identified in the IG report as the starting point for separations as the critical one.

“That report is thorough and it’s not controverted. I’m not hearing that that report is inaccurate, [or that] we ought to abandon it,” Sabraw said. “It appears to be 100 percent factual, and the report says this separation policy started in July of 2017.”

Sabraw added that it would seem that when there is “an allegation of wrong on this scale” a full accounting of that wrong goes to “the essence of the case.”

“So much of what is happening in these kinds of cases is exactly that,” he said. “It’s information that the public under our law is entitled to and there’s no way to get to that absent the relief that the plaintiffs are requesting.

“It seems to me that the principal legal relief they’re asking for is the accounting, so that we know what the government is doing and the scope of it—everyone, all of us.”