WASHINGTON (AP) — Tony Ornato, who served as White House deputy chief of staff under Donald Trump, is expected to appear Tuesday for an interview before the House select committee investigating the Jan. 6 riot on Capitol Hill. said a person familiar with the panel’s plans.

Ornato is considered a key witness to the events surrounding the Capitol Hill riot and will likely be questioned about the testimony of star witness Cassidy Hutchinson, who was an aide to former White House chief of staff Mark Meadows.

Hutchinson testified over the summer that Ornato told him Trump was angry when his Secret Service detail refused to take him to the Capitol as his supporters descended on the building. She said Ornato told her that Trump jumped behind the wheel of the van he was in, demanding a ride down Pennsylvania Avenue to the Capitol.

Ornato’s attorney, Kate Driscoll, would not specifically address his appearance Tuesday, but told NBC News: “Mr. Ornato continues to cooperate with the January 6 select committee investigation.»

Committee aides declined to comment on the highly anticipated interview, which was first reported by The New York Times.

Secret Service officials have questioned Hutchinson’s testimony, prompting the committee to bring in some of them for questioning under oath. Ornato has already testified in front of the committee, but Hutchinson’s testimony prompted the committee to call him back.

After serving in the Trump White House, Ornato was deputy director of the Secret Service until he left the agency in August to work in the private sector.

Before Thanksgiving, the committee’s investigators spoke with Bobby Engel, who led the former president’s protective team. And in early November they were scheduled to meet with a Secret Service agent who was in the lead car of Trump’s motorcade on the day of the riots.

Meanwhile, former Trump adviser Kellyanne Conway met with the committee for nearly five hours Monday. Conway served as a senior adviser to Trump from the start of his term until August 2020. She decided to leave the administration because she said she needed to focus on her family. She was also a campaign manager for Trump’s 2016 presidential bid.

Although Conway was not working for Trump on January 6, 2021, The Washington Post, citing 15 Trump advisers, members of Congress, Republican officials and others, reported that he called an aide who was with the president that day and told him he would join others in urging Trump to tell his supporters to stand down. Conway also told the aide that Washington Mayor Muriel Bowser’s office called her asking for her help getting Trump to call in the National Guard, The Post reported.

The committee is expected to publish a final report on its investigation before the end of the year, before the new Congress convenes in January. The panel is not expected to exist in the new GOP-controlled House next year.