Republican senators on Tuesday (7 February) voted to formally silence Democratic colleague Elizabeth Warren after she read out a letter from Martin Luther King's widow during a debate over Senator Jeff Sessions' nomination for attorney general. The 1986 letter had criticized Sessions's record on civil rights.

The republican majority leader Mitch McConnell objected to Warren's move saying that she had broken rules of the Senate which prohibit one member of the senate from impugning another. Senators voted 49-43 to ratify a ruling in McConnell's favour.

"The senator has impugned the motives and conduct of our colleague from Alabama, as warned by the chair," the House majority leader said.

Later on in the night, Warren read the letter on Facebook Live. "During the debate on whether to make Jeff Sessions the next Attorney General, I tried to read a letter from Coretta Scott King on the floor of the Senate," she said.

"The letter, from 30 years ago, urged the Senate to reject the nomination of Jeff Sessions to a federal judgeship. The Republicans took away my right to read this letter on the floor - so I'm right outside, reading it now."

Meanwhile, the Democrats said that the Republicans were selectively enforcing the rule. They also took to social media using the hashtag #LetLizSpeak. In a statement, the Democratic National Committee said that it was a "sad day in America when the words of Martin Luther King Jr's widow are not allowed on the floor of the United States Senate".

McConnell said on the Senate floor: "She was warned. She was given an explanation. Nevertheless, she persisted,"

The majority leader's office said that the Democratic lawmaker is now barred from speaking on the Senate floor for the rest of the debate about Sessions.