Mueller’s unusual back-to-back testimony in front of the House Judiciary and Intelligence committees is likely to be the most highly anticipated congressional hearing in years, particularly given Mueller’s resolute silence throughout his two-year investigation into Russian contacts with President Donald Trump’s campaign. Mueller never responded to angry, public attacks from Trump, nor did he ever personally join his prosecutors in court or make announcements of criminal charges from the team.

His sole public statement came from the Justice Department podium last month as he announced his departure, when he sought to explain his decision to not indict Trump or to accuse him of criminal conduct. He also put lawmakers on notice that he did not ever intend to say more than what he put in the 448-page report.

“We chose those words carefully and the work speaks for itself,” Mueller said May 29. “I would not provide information beyond what is already public in any appearance before Congress.”

Those remarks did little to settle the demands for his testimony. The two committees continued negotiations that had already been going on for weeks, saying they still wanted to hear from Mueller no matter how reluctant he was.

“When you accept the role of special counsel in one of the most significant investigations in modern history you’re going to have to expect that you’re going to be asked to come and testify before Congress,” House Intelligence Committee Chairman Adam Schiff, D-Calif., told reporters shortly after the announcement.

Trump himself simply tweeted, “Presidential Harassment!”

In the report issued in April, Mueller concluded there was not enough evidence to establish a conspiracy between Trump’s presidential campaign and Russia, which was the original question that started the investigation. But he also said he could not exonerate Trump on obstruction of justice. The report examined several episodes in which Trump attempted to influence the investigation.

Democrats say it is now the job of Congress to assess the report’s findings. Lawmakers are likely to confront Mueller on why he did not come to a firm conclusion on obstruction of justice. They are also likely to seek his reaction to a drumbeat of incessant criticism from the president and ask for his personal opinion about whether Trump would have been charged were he not the commander-in-chief.

Schiff and House Judiciary Committee Chairman Jerrold Nadler said they issued the subpoenas Tuesday, and Mueller agreed to testify pursuant to those subpoenas. In a letter to Mueller accompanying the subpoenas, the committee chairmen said “the American public deserves to hear directly from you about your investigation and conclusions.”

Schiff said there will be two hearings “back to back,” one for each committee, and they will also meet with Mueller’s staff in closed session afterward.

The Justice Department declined to comment.

Republicans have criticized Democrats for their continuing investigations of the president. House Minority Leader Kevin McCarthy, R-Calif., questioned why they would still want to hear from Mueller after the lengthy report was issued. “He said he didn’t want to talk to us anymore, didn’t he?”

But Georgia Rep. Doug Collins, the top Republican on the Judiciary panel, has said he has no objections to Mueller’s testimony.

“May this testimony bring to House Democrats the closure that the rest of America has enjoyed for months, and may it enable them to return to the business of legislating,” Collins said.