Demonstrators march through the streets of Winston-Salem, N.C., on July 13, 2015, after the beginning of a federal voting rights trial challenging a 2013 state law. (Chuck Burton/AP)

— “Our country has changed,” Chief Justice John G. Roberts Jr. wrote in 2013, when the Supreme Court freed Southern states from the requirement that federal authorities approve any proposed ­election-law change in order to ensure minority voters were not harmed.

Republican lawmakers in North Carolina appeared to take that as a go signal; they immediately unveiled a previously private plan to overhaul the state’s voting procedures.

A 14-page bill that would require voters to show specific kinds of identification was replaced with a 57-page omnibus package. It rolled back or repealed a number of voting procedures that civil rights leaders say had made the state a leader in increasing African American voter turnout. It was approved along party lines.

What is known as House Bill 589 has been the subject of court battles ever since. A federal trial nearing completion here on the state’s changes is being watched nationwide for signals about what the Voting Rights Act of 1965 still means after the Supreme Court’s 5-to-4 decision two years ago in Shelby County v. Holder.

Civil rights icon and congressman John Lewis (D-Ga.) speaks at an event celebrating the 50th anniversary of the Voting Rights Act of 1965 in Washington on Thursday. (Gary Cameron/Reuters)

Lawyers and civil rights officials suing North Carolina speak in historic and apocalyptic terms about the case, to the annoyance of state officials. The striking slogan they have adopted: “Our Selma.”

It is an indication that the legal battle represents more than simply plumbing the limits of the Voting Rights Act and the importance of minority turnout in the 2016 presidential campaign.

It takes place in the midst of a renewed national conversation on race: tensions over shootings by white police officers, the slaying of nine worshipers in an African American church in neighboring South Carolina, the fight over Confederate symbols and tributes.

The Rev. William Barber II, president of the North Carolina NAACP, tied it all together in a recent call with reporters by noting a proposal that would restrict localities from doing away with Confederate symbols without the approval of the legislature.

“Basically the context of this state is a place where we would rather protect images of our racist past than to address voter suppression in the present,” he said.

But Karl S. Bowers, a private attorney representing Gov. Pat McCrory (R), said the state’s past is irrelevant to what he contends are mundane changes that do not single out minorities for disparate treatment.

“North Carolina, like many other states all over the country, has a terrible history of discrimination. Nobody in this courtroom disputes that,” Bowers said in his opening statement. “But the history of North Carolina is not on trial here.”

The NAACP, the League of Women Voters and the American Civil Liberties Union are among those suing the state. They are supported by the Obama administration, and Justice Department lawyers have asked that U.S. District Judge Thomas D. Schroeder take the rare step of returning North Carolina to federal oversight, a process known as “pre-clearance.”

Penda D. Hair, a lawyer for Advancement Project, a civil rights organization, told Schroeder during opening arguments that her clients “understand that this case is a pivotal moment in history.

The trial, Hair said, “will have a lasting and decisive impact on the voting acts of African Americans and Latinos in North Carolina and an impact on the Voting Rights Act itself.”

The changes at issue sound tame and almost inconsequential, compared with the poll taxes, literacy tests and voter intimidation tactics that led to passage of the Voting Rights Act.

Instead: a reduction in the number of days of early voting, disallowing people to register and vote on the same day, not counting votes that were cast in the wrong precinct and ending the practice of pre-registering teenagers before they become 18. (The voter identification piece of the legislation was modified by lawmakers this year and is not part of the current case.)

“What is the dastardly thing that North Carolina has done that has been equated to the terrible things that happened in Selma?” lawyer Thomas C. Farr asked rhetorically to Schroeder, who is deciding the case without a jury. “What they did, your honor, is they enacted election regulations that represent the majority rule in most of the states in this country.”

Before the Supreme Court’s decision in Shelby County , North Carolina would not have been able to enact the changes without the approval of the Justice Department or a panel of judges. It was among a group of mostly Southern states that were forced to receive pre-clearance because of past discrimination.

But in its last reauthorization of the Voting Rights Act, Congress relied on the same data it had used for decades to decide which states must seek pre-clearance. Roberts said that was not good enough when imposing such a burden on the states.

He noted that Section 2 of the Voting Rights Act remained in place to protect minorities against policies that result in the denial or abridgement of voting rights by minorities.

But under Section 2, the burden of proof shifts to the challengers, who must show that the policies were intended to hurt minorities.

“The discriminatory result of HB 589 was neither accidental nor unforeseen,” Justice Department lawyer Catherine Meza told the court. The challengers have presented evidence that lawmakers requested information about which voters used the procedures that they proposed to scale back or do away with and knew that African Americans and Latinos disproportionately relied upon them.

The changes were in effect for the 2014 election, and plaintiffs presented evidence that minority voters who would have been allowed to participate in previous elections were left out or did not have their votes counted, because they were in the wrong precinct.

The lawmakers who backed the bill said at the time that worries about voter fraud and the integrity of the system motivated their actions. But they have declined to testify at the trial and said their communications were privileged and need not be disclosed.

“The elected officials said they were doing this for transparency and voter integrity, and then when we brought this case they claimed legislative privilege and won’t subject themselves to come under oath and explain why they did it,” said Daniel Donovan, a private attorney representing the challengers.

But the 2014 election provided an inconvenient fact for the challengers: Despite dire predictions from experts about what the changes would mean for minority turnout, African American participation actually increased from the last non-presidential-election year, 2010.

“I don’t find any evidence of a negative impact,” said M.V. “Trey” Hood, a University of Georgia political science professor who testified for the state.

The challengers said that a 2014 U.S. Senate race that set a record for campaign spending increased interest beyond that of the 2010 race — and that overcoming obstacles does not mean that the obstacles were not put there intentionally.

The case raises the issue of whether a state may ever cut back on procedures that were enacted, usually when Democrats were in charge, to increase the minority vote. Farr pointed out that many states — Hillary Rodham Clinton’s adopted state of New York, for example — do not offer early voting.

Many states do not allow people to register and vote on the same day, saying a waiting period is necessary to verify the information given. And Farr presented witnesses who said other states have African American participation as high as North Carolina’s without the accommodations at stake in the case.

Schroeder had indicated that he will be trying to differentiate between whether the changes imposed a discriminatory burden on the right to vote or simply made it more inconvenient for some. Closing arguments are scheduled for Friday, and he will probably take weeks to sort through the conflicting testimony before rendering a decision.

He had earlier denied challengers an injunction that would have kept the changes from going into effect for the 2014 election. An appeals court overturned part of his decision, but it was overruled by the Supreme Court.

The issue of what Section 2 of the Voting Rights Act requires seems likely to return to the high court. There are two cases from Texas — one involving reapportionment, another concerning a voter ID law, that has united the Justice Department with challengers.

But North Carolina’s changes are the most sweeping and comprehensive. For the state’s legislators, the autonomy returned to them through the Shelby decision is the natural order in a federal system. For the NAACP’s Barber, “it is all our fears coming true.”