Mounting an opera about voting rights in the nation’s capital is “so fitting and appropriate,” said Representative John Lewis, a Democrat from Georgia, whose skull was fractured by a state trooper during the 1965 march in Selma, Ala., that became known as Bloody Sunday, and who said he had been surprised to learn that he was a character in the opera.

“There’s a great deal of discussion going on in the country about what the Supreme Court did when it put a dagger in the heart of the Voting Rights Act that was passed and signed into law 50 years ago,” Mr. Lewis said in a telephone interview. “The issue is so present right now.”

Soloman Howard, a rising young bass who is singing the roles of Douglass and King, said that it was difficult not to hear contemporary echoes in the voting rights scenes — and noted the recent uproar over Alabama’s move to close offices that issue drivers’ licenses, including in predominantly black neighborhoods, after moving to require people to show photo identification to vote. “It’s still very much alive,” he said of the issue.

One dramatic thread that has been expanded in the revised opera seems especially timely in the age of the Black Lives Matter movement: the killing of Jimmie Lee Jackson, the 26-year-old civil rights marcher whose death in 1965 at the hands of a state trooper led to the historic marches in Selma. Three years after the opera’s San Francisco premiere, a former state trooper named James Bonard Fowler pleaded guilty to a misdemeanor charge of manslaughter in the shooting and was sentenced to six months in prison. Mr. Fowler, who died in July at 81, now has a scene in the opera.

The changes to the opera were brought about by a confluence of events. In 2012 the Guthrie Theater in Minneapolis devoted a season to works by Mr. Hampton, the British playwright who wrote “Les Liaisons Dangereuses,” among other plays, and asked him for a new piece. He turned his “Appomattox” libretto into a more sweeping drama that delved more deeply into the civil rights era and its contemporary resonances.