U.S. Sen. Jeff Merkley (D-Oregon) has been the leading critic in Congress of the Trump administration policy that has separated more than 2,000 immigrant children from their parents at the U.S.-Mexico border.

Merkley's Facebook video in early June of being turned away from a shelter housing kids who'd been separated from their parents raised the profile of the issue earlier this month.

Tomorrow, he and fellow Democrats are opting for a more traditional approach—holding an unofficial hearing in the Senate.

Republicans control the Senate and the gavels for all formal committee hearings; they have not scheduled a hearing on the issue, so Merkley and the Democrats are proceeding regardless. They'll hear from nonprofit leaders who are working at the border.

"The administration has proven unwilling or unable to account for the thousands of children in its custody or provide a plan to reunite them with their families," says the press advisory explaining the reason for the hearing.

"Senators will examine the impact of the family separation policy's ongoing trauma on children, hear parents' stories, and look at the implications and chaos caused by the administration's actions."