Last night, during a debate over President Trump’s nomination of U.S. Senator Jefferson Beauregard Sessions III of Alabama—a man deemed, in a bipartisan vote of the Senate Judiciary Committee, to be too racist for the federal bench in 1986—to be attorney general, U.S. Senator Elizabeth Warren read a letter from Coretta Scott King, Martin Luther King Jr.’s widow, written in objection to Sessions’s elevation to the bench.

Here is the entire letter, plus the ten-page statement King submitted in 1986, that Warren thought was relevant to Sessions’s nomination to the top law enforcement position in the country, in which capacity he will oversee the Department of Justice’s Civil Rights Division and have the ability to enforce—or not—things like the Voting Rights Act.

If you don’t feel like reading all of that, here is a highlight:

“I write to express my sincere opposition to the confirmation of Jefferson B. Sessions as a federal district court judge for the Southern District of Alabama. My professional and personal roots in Alabama are deep and lasting. Anyone who has used the power of his office as United States Attorney to intimidate and chill the free exercise of the ballot by citizens should not be elevated to our courts. Mr. Sessions has used the awesome powers of his office in a shabby attempt to intimidate and frighten elderly black voters. For this reprehensible conduct, he should not be rewarded with a federal judgeship.”

Senate Majority Leader Mitch McConnell decided that, by reading this letter, Senator Warren was violating an arcane Senate rule prohibiting senators from impugning the integrity of each other, even though she was quoting the words of a civil rights icon.

From The New York Times’s account:

Across the room, Senator Mitch McConnell, the majority leader, had stepped forward with an objection, setting off an extraordinary confrontation in the Capitol and silencing a colleague, procedurally, in the throes of a contentious debate over President Trump’s cabinet nominee.

“The senator has impugned the motives and conduct of our colleague from Alabama, as warned by the chair,” Mr. McConnell began, alluding to Mrs. King’s letter, which accused Mr. Sessions of using “the awesome powers of his office in a shabby attempt to intimidate and frighten elderly black voters.”

Mr. McConnell called the Senate to order under what is known as Rule XIX, which prohibits debating senators from ascribing “to another senator or to other senators any conduct or motive unworthy or unbecoming a senator.”

When Mr. McConnell concluded, Ms. Warren said she was “surprised that the words of Coretta Scott King are not suitable for debate in the United States Senate.” She asked to continue her remarks.

Mr. McConnell objected.

“Objection is heard,” said Senator Steve Daines, Republican of Montana, who was presiding in the chamber at the time. “The senator will take her seat.”

By a 49–43 vote, the senators present then upheld Daines’s decision, silencing Warren for the duration of the Sessions’s debate (and, assuming she has presidential aspiration, effectively writing her 2020 campaign an early in-kind contribution). It was a churlish, childish display, made all the worse by the fact that this is Black History Month and that the senator at the heart of this debate has a decades-long history of racially charged allegations against him.

As an explanation, McConnell later said this, which quickly became a meme that spread far and wide: “She was warned. She was given an explanation. Nevertheless, she persisted.”

Like every other Republican present, North Carolina senators Richard Burr and Thom Tillis voted to shut Warren up.

Sessions is expected to be confirmed today.