On December 13, 1922, NAACP official James Weldon Johnson sent an open letter to every senator in the U.S. Senate.
The letter was sent in response to the Democrats' successful filibuster of the Dyer-Anti Lynching Bill and pointed out that four blacks were lynched since the bill died in the Senate.
The bill was introduced by Republican Congressman Leonidas Dyer.
In his letter Johnson wrote, "the blood of these victims rests upon the Democrat senators who have obstructed even discussion of the measure to remedy the condition."
H/T Ken Raymond