A federal judge appeared poised on Thursday to order the government to fully account for all migrant families that were separated before and after the Trump administration formally announced it's "zero-tolerance" policy.

U.S. District Judge Dana Sabraw ordered the administration to end the family separation policy on June 26, 2018, and to reunite nearly 3,000 children who were being held in the Department of Health and Human Services at the time of his order.

But the ACLU is now asking the judge to expand his order to include families that were separated during the previous year, following media reports and an inspector general report that revealed the administration had an unofficial family separation policy in place as far back as July 2017.

Department of Justice attorney Scott Stewart fought back against the ACLU request during a court hearing before Sabraw on Thursday, arguing that the government has gone "above and beyond" to facilitate the reunification of thousands of children with their parents rather than fight the judge's order "tooth and nail."

Requiring the government to identify potentially thousands of children that were separated in the previous year, Stewart said, would "blow the case into some other galaxy" and could force Justice to take a different approach to the lawsuit.

"I'm just not sure that we can keep going that way," Stewart said.

Sabraw explained that the ultimate goal of the lawsuit is to "bring to light" the wrongs committed by the administration's family separation policy, even if that requires government agencies taking on the difficult task of poring through records to identify all children that were separated.

He said his original order only required the reunification of children in government custody at that time because the size and scope of the family separation policy was unknown at that time.

"No one but a few in the government knew that these separations had been going on nine or 10 months before, and that hundreds if not thousands of children were," being separated, Sabraw said. "The court didn’t know that and plaintiffs didn’t know that, and I don’t think government counsel knew that."

Sabraw did not rule from the bench, but already started discussing what the next steps could look like.

ACLU attorney Lee Gelernt said he was prepared to organize a steering committee of volunteers and pro bono attorneys to help track down all separated parents and children, just as they've been doing to find the more than 2,800 families that have been at the core of the lawsuit. But he said officials at the Department of Homeland Security, which carried out the separations, and the Department of Health and Human Services, which cared for the separated children, need to be involved since they're the ones who hold all the information on each family's case.

"We are prepared no matter how big the burden is," Gelernt said.

Sabraw asked whether the government could tap Cmdr. Jonathan White, an HHS official, to lead DHS and HHS in their reunification efforts. White oversaw the government efforts to reunite the original group of 2,800 children, and has drawn praise from the judge, the ACLU and even members of Congress for his work.

And while Sabraw said he was not sure how the additional reunifications would eventually be carried out, he said the first step had to be simply getting a full list of every family that was separated.

"It's important to recognize that we're talking about human beings," Sabraw said. "Every person needs to be accounted for."

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