House Judiciary Chairman Jerry Nadler said he and the rest of the committee will hear former White House counsel Don McGahn's testimony, one way or another.

"Let me be clear: This Committee will hear Mr. McGahn’s testimony, even if we have to go to court to secure it," he said. "We will not allow the President to prevent the American people from hearing from this witness."

He continued: "We will not allow the President to block congressional subpoenas, putting himself and his allies above the law. We will not allow the President to stop this investigation, and nothing in these unjustified and unjustifiable legal attacks will stop us from pressing forward with our work on behalf of the American people."