House Judiciary Committee Chairman Jerrold Nadler, D-N.Y., on Monday subpoenaed former White House counsel Don McGahn to testify publicly next month following last week’s release of Special Counsel Robert Mueller’s report on the Russia investigation.

Nadler described McGahn, who stepped down as White House counsel in October 2018, as “a critical witness to many of the alleged instances of obstruction of justice and other misconduct described in the Special Counsel’s report.”

“The Special Counsel’s report, even in redacted form, outlines substantial evidence that President Trump engaged in obstruction and other abuses,” Nadler said. “It now falls to Congress to determine for itself the full scope of the misconduct and to decide what steps to take in the exercise of our duties of oversight, legislation and constitutional accountability.”.

Nadler added that he has requested McGhan to appear before the committee on May 21 and has set a May 7 deadline for him to provide documents related to the Mueller investigation. The statement and subpoena came as House Speaker Nancy Pelosi, D-Calif., in a conference call urged rank-and-file Democrats to let the investigative process establish facts before talking up impeachment.