Story highlights Booker, Lewis, and Richmond testified at the hearing against the nomination of Jeff Sessions

"I never seen anything like this," Lewis told reporters after the hearing

Washington (CNN) Democrats on Capitol Hill left the Senate Judiciary Committee hearing room seething Wednesday. But it was not the testimony from witnesses that caused the only stir.

Members of Congress and outside progressive groups were visibly disturbed and disappointed that several members of the Congressional Black Caucus were not given the courtesy of testifying earlier in the committee proceedings on the nomination of Sen. Jeff Sessions -- President-elect Donald Trump's nominee for attorney general -- and instead left to testify at the end of the second day of hearings alongside outside witnesses.

"To have a senator, a House member and a living civil rights legend testify at the end of all of this is the equivalent of being made to go to the back of the bus," said Rep. Cedric Richmond of Louisiana, causing applause from several members of the audience in an already palpably tense hearing room.

"I've been here almost 30 years and never seen anything like this," Rep. John Lewis told a group of reporters after the hearing.

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Things got off to a rocky start earlier in the week when Politico first reported that Sen. Dianne Feinstein had requested a "members-panel" in order for three black lawmakers -- Lewis, Richmond and New Jersey Sen. Cory Booker -- to testify at Sessions' confirmation hearing this week.

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