Simmering debate on the future of the filibuster has increased further now that President Biden has endorsed proposals to force senators who filibuster to hold the Senate floor, in the hopes that the exhausting ritual will diminish the number of filibusters obstructing legislation. The stakes are high, given that a voting rights bill looms in the near future. But even proponents of reform who point to the filibuster’s long history of hindering civil rights measures leave out a crucial and gruesome chapter in the making of the modern filibuster.

The most famous such use of the filibuster was against the Civil Rights Act of 1964. Opponents of the Act filibustered for a record-breaking 60 working days. Millions of Americans watched as CBS’s Roger Mudd reported live from the steps of the Capitol on white Southern senators’ efforts to kill the legislation.

But the modern filibuster’s first civil rights fatality actually occurred decades earlier in the searing 1922 defeat of the Dyer Anti-Lynching Bill. The Senate’s abandonment of this landmark legislation in the history of anti-Black violence is little remembered today, but it set a path for partisan and ideological battles in the century since and continues to reverberate in our legal system.

Lynch mobs murdered more than 4,000 Black people between the end of Reconstruction and the middle of the 20th century. Activists like Ida B. Wells and organizations like the NAACP worked to expose the savagery of lynching, to debunk the pervasive myth that lynch mobs avenged the rape of white women and to revive public and legislative concern for Black lives for the first time since the retreat from Reconstruction. Anti-Black violence had risen to grim new peaks during the horrific Red Summer of 1919. The deadliest race riot erupted in Elaine, Ark., where 500 heavily armed soldiers, local law enforcement and white vigilantes killed hundreds of Black sharecroppers who had dared to join forces in the sale of the year’s valuable cotton crop.

Resurrecting the GOP’s history as the party of Lincoln and Reconstruction, a contingent of liberal Republicans renewed what had been a sporadic push for anti-lynching legislation. Rep. Leonidas Dyer’s (R-Mo.) anti-lynching proposal was the most ambitious to date. The bill would have empowered the federal government to prosecute private actors who participated in lynchings and fine counties that failed to prevent the violence. In the wake of the Republican electoral sweep in 1920, Dyer garnered support from his House colleagues and the Senate Judiciary Committee. President Warren G. Harding seemed to offer support, too, even if lukewarm. The Dyer Bill passed in the House on Jan. 26, 1922. The NAACP — barely a decade old — claimed the passage as a great legislative victory.

Despite this substantial backing, the bill ultimately died a procedural death at the hands of a filibuster led by Southern Democrats. Indeed, the Dyer Bill drama inaugurated a new era for the legislative tactic. Filibusters had been largely ineffective until the 1880s, when politicians from both sides of the aisle began to use them successfully to delay or amend disfavored legislation. White Southerners in particular saw the tactical utility of the maneuver, invoking it to block a voting rights bill in 1891. But after anti-militarists led by Sen. Robert La Follette of Wisconsin used a filibuster to block President Woodrow Wilson’s proposal to arm merchant ships against German U-boat attacks during World War I, the Senate moved to adopt a new parliamentary policy. The rule of “cloture,” adopted in 1917, enabled a two-thirds vote to close debate and overcome the antics of a determined minority.