A Health and Human Services official insisted that the agency is not responsible for ensuring the safety of unaccompanied migrant children once they leave its care — and pleaded with senators on Thursday not to force it to take on the responsibility.

“Please don’t make us a law enforcement agency,” said Jonathan White, testifying on behalf of HHS at a hearing held by the Senate Homeland Security and Government Affairs subcommittee on investigations. “I think it’s very important that HHS remain the agency tasked with the best interests of the child rather than to assign it enforcement duties.”

White, a career government official and commander in the U.S. Public Health Service Commissioned Corps, bore the brunt of the questioning from visibly frustrated senators who at times raised their voices at him, only to later apologize for their harsh tone.

Although White was joined on the panel by witnesses from the Department of Justice and the Department of Homeland Security, the senators' attention was primarily on him. Children who cross the U.S.-Mexico border without an adult are placed in government-run shelters overseen by HHS. But after they are turned over to the care of an adult sponsor, there is no formal government system in place to ensure their welfare or safety.

Sens. Rob Portman (R-Ohio) and Sen. Thomas R. Carper (Del.), the subcommittee’s chairman and ranking Democrat, released a report Wednesday detailing ways in which they believe HHS, and the federal government more broadly, has failed to protect these children. At the hearing, the senators said they are considering legislation that would require HHS to take on a greater role in ensuring the well-being of minors after they leave the shelters.

Yet by the end of the hearing, the senators and White were no closer to an agreement on how — or even if — these children should be monitored when they’re no longer physically in the government’s custody.

“We have neither the authorities nor the appropriations to exercise that degree of oversight after minors exit (government) care,” White told the senators.

“As you know Commander White, this is where we have a difference of opinion,” said Portman. “We believe Congress has given you that authority. And by the way if you don’t, who does?”

This debate began during the Obama administration when an influx of migrant children traveling without their parents overwhelmed resources and drew sharp attention to the government’s handling of the kids. During that time, it was learned that HHS had turned eight children over to human traffickers in Ohio, so senators began asking why no one in the government was accountable for knowing the children’s whereabouts.

The problem has only gotten worse, Portman and Carper said in their report, since the Trump administration began its now-ended policy of family separations at the border — sending even more children to overcrowded HHS shelters.

In 2015, HHS agreed to attempt to reach a child or their sponsor 30 days after they leave the shelters. But if they cannot be reached, there is no further action required of the agency.

This April, HHS revealed that of the more than 7,000 calls made to sponsors over three months in 2017, officials couldn’t make contact with nearly 1,500 children. At the hearing, Portman asked White for similar data from 2018. White assured him he’d get those numbers in the next two weeks.

Still, at the hearing, White stressed that HHS is not equipped to be the primary agency responsible for tracking down the kids.

White said HHS had no “custodial jurisdiction” once the children left the shelters. He also explained that the children who couldn’t be reached in those follow-up calls are not “lost” in the traditional sense, but rather many of the adult sponsors are undocumented and fear any additional contact with the U.S. government.

"Many individuals come out of the shadows to take their child from us, and some of them return to the shadows,” White said. “These are individuals who are living undocumented in the United States in most cases, and they believe they have cause to fear us.”

Senators from both parties didn’t accept that.

“Let’s be really clear here. If a sponsor isn’t answering a phone call, you don’t know where that child is,” Sen. Maggie Hassan (D-N.H.) said. “So you can’t tell us there’s nobody lost.”

“Of course there are lost children — and that’s the whole point here,” Portman said. “No one’s responsible. Why don’t they have to take the call? What does the sponsor agreement mean if they don’t have to take a call at least?”

When adult sponsors, who are mostly parents, remove kids from the shelters they sign an agreement with HHS that they’ll take them to their immigration hearing, but more than half don’t show. “Who enforces that sponsor agreement?” Portman continued. “And your answer to me is going to be nobody.”