President Donald Trump’s short-lived policy of separating families entering the country illegally worsened the U.S.’s already troubled efforts to protect unaccompanied migrant children from trafficking and abuse, a bipartisan Senate investigation found.

“The Trump administration took steps that exacerbated” problems that emerged during Barack Obama’s administration, the Senate’s Permanent Subcommittee on Investigations said in a report released Wednesday that examines the government’s treatment of what it calls unaccompanied alien children.

The Senate panel will hold a hearing on Thursday to grill officials from the Department of Health and Human Services, Customs and Border Protection, Immigration and Customs Enforcement and the Justice Department, on the flaws in the program to care for migrant children and how the family separation policy made matters worse.

“The problems that exist today began during the previous administration and have continued under this one,” said Ohio Republican Rob Portman, the subcommittee’s chairman. “These federal agencies must do more to care for unaccompanied minors and ensure they aren’t trafficked or abused.”

Delaware Senator Tom Carper, the panel’s top Democrat, said in a statement that the Trump administration “continues to make an already challenging reality for migrant children even more difficult and more dangerous.”

28 Children Ran Away

At the subcommittee’s most recent hearing in April, HHS official Steven Wagner said the agency had been “unable to determine with certainty the whereabouts” of 1,475 children, about one-fifth of the 7,635 it had attempted to contact during the final three months of 2017. Wagner said the office also learned that 28 children “had run away.”

Ahead of Thursday’s hearing, HHS told the subcommittee’s staff it was unable to provide data from this year “because of the toll the family reunification effort is taking on HHS’s resources.”

The HHS along with the Department of Homeland Security and the Justice Department issued a joint statement late Wednesday afternoon blasting what they described as a “misleading report” that includes “fundamental misunderstandings of law and policy related to the safety and care” of what the government refers to as unaccompanied alien children, or UACs, and does “not focus on the real challenges with preventing children from being smuggled and trafficked in the first place, nor does the subcommittee capture the extensive work done to protect UACs once they arrive here.”

As the Trump administration separated parents and children who crossed the border illegally in May and June, it designated the children UACs and put them into the HHS shelter system, which was already under Senate investigation for losing track of children who were released to sponsors.

Adding more than 2,500 children to the HHS system — some of whom were “tender age,” under five years old– has only created more difficulties for the government. “These burdens on HHS — processing and housing these additional UACs and working to reunite the families — have stretched thin its already-limited resources for the UAC program,” the Senate report said.

The report concludes that no federal agency claims legal responsibility for ensuring that the children aren’t being trafficked or abused after being placed with a sponsor. Leaders from the Office of Refugee Resettlement, which manages the HHS shelter system, told the panel’s staff that the children end up in a “legal no man’s land,” according to the report.

The government has few options to check in on children or to ensure that they appear in immigration court because no federal agency tracks the children after they’re placed with sponsors.

The report also said that Homeland Security and HHS have dragged their feet in producing a care plan for the children. They missed their own deadline by 17 months before providing a document to the subcommittee in late July. That plan didn’t address “significant problems” that the Government Accountability Office has identified, according to the report.

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