When Senate Majority Leader Mitch McConnell silenced Elizabeth Warren last week as she was reading Coretta Scott King’s 1986 letter denouncing Jeff Sessions, he jogged the memory of another Massachusetts Democrat, Rep. William R. Keating.

“I went to bed that evening seeing what was occurring,” Keating said in an interview, “and when I woke up in the morning, my mind immediately went back to the outrage of an amendment that had been passed in the House,” almost entirely with Republican votes.

The amendment, introduced by Rep. David Schweikert (R-Ariz.) and approved on May 9, 2012, was aimed at preventing the Justice Department from using its funds “to bring any action against any state for implementation of a state law requiring voter identification.”

In other words, even if the Department of Justice thought a voter ID law discriminated against African Americans or Latinos, it could not sue to protect them.

In defending the amendment, Republicans sounded like the old Southern segregationist Democrats who stood up for states’ rights — meaning, among other things, their “right” to disenfranchise people of color. The segregationists loved to denounce Washington, and that’s what Schweikert did that day.

(Bastien Inzaurralde/The Washington Post)

“I’m tired of this,” he said, “and I think the American people are tired of there being this battle between the federal government suing our states and costing the residents, the citizens of these states, these litigation costs.”

The amendment never made it through the Senate, but for Keating, the episode underscored the dangers that Sessions poses as attorney general. During the Obama years, the Justice Department tried to block state laws plainly aimed at suppressing turnout among minority groups. Now, voting rights advocates will no longer have the attorney general as their ally. “Acts of omission,” noted Keating, a former prosecutor, are often as serious as “acts of commission.”

Cutting off Warren under the irregularly observed Rule 19 was an outrage on many levels. Under the rule, senators cannot “impute to another senator or to other senators any conduct or motive unworthy or unbecoming a senator.” But the confirmation of then-Sen. Sessions was the very focus of the discussion. Carried to its logical conclusion, the idea that a senator can’t speak ill of a president’s nominee who happens to be a senator could shut down debate altogether.

But what Warren was reading when she was muzzled goes to the heart of the matter. Here is the key passage of King’s letter opposing Sessions’s nomination as a judge in 1986: “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.”

The Senate rejected Sessions as a judge 31 years ago. But now that he is our chief law enforcement officer, holding him accountable for how he vindicates or undermines civil rights and voting rights is a central task. So is rallying against all efforts in Republican-controlled states to pass new laws restricting the franchise, as many of them already have. The Department of Justice can’t be counted on to stop them.

And the struggle for democracy is also at stake in the fight over President Trump’s nomination of Judge Neil Gorsuch to the Supreme Court. Senate Minority Leader Charles E. Schumer told MSNBC’s Rachel Maddow last week of “an eerie feeling” he had when he spoke with Gorsuch.

“Here was a judge, well-groomed, intelligent, very polite, very, very articulate, who wouldn’t give his views on anything,” Schumer said. This reminded him of someone else.

“Justice [John] Roberts, then-Judge Roberts, assured us he would call balls and strikes,” Schumer said. “He gets in office, and his court does Citizens United, a huge break with precedent that ruins, ruins the politics of America. He repeals, basically, the Voting Rights Act by eliminating Section 5 . . . and I am very worried that Judge Gorsuch is similar.”

The court’s action on voting rights made it far harder to police abuses, while Citizens United undercut the regulation of big money in politics. So if you wonder why there is skepticism among liberals about Gorsuch, consider what conservative Supreme Court justices have already done. Think also about what it would mean to have a Supreme Court, an attorney general and a Congress all prepared to gut what had long been the basic rules of democracy. Bill Keating is not alone in his nightmares.

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