GEOFF BENNETT: The U.S. Supreme Court today struck down Republican-drawn congressional districts in Alabama that civil rights activists say discriminated against Black voters.

The ruling was a surprising departure from court opinions over the past decade narrowing the scope of the Voting Rights Act.

Chief Justice John Roberts wrote the majority opinion and was joined by the three liberal justices, as well as conservative Justice Brett Kavanaugh.

To help us understand the significance of all this, we're joined by "NewsHour" Supreme Court analyst Marcia Coyle and redistricting expert David Wasserman of The Cook Political Report With Amy Walter.

With a welcome to you both, Marcia, we will start with you.

The chief justice in the opinion wrote that there were legitimate concerns that the Voting Rights Act -- quote -- "may impermissibly elevate race and the allocation of political power within the states," but he added: "Our opinion today does not diminish or disregard these concerns.

It simply holds that a faithful application of our precedents and a fair reading of the record before us do not bear them out here."

What is the court saying with this ruling?

MARCIA COYLE: I think the chief justice is saying that the majority is aware that, whenever you deal with racial classifications, whether it's in redistricting or in other contexts, there is that concern that race may dominate.

And so he's reassuring everyone that there really is a totality-of-circumstances test for Section 2, and that the court's precedents in this area have imposed limitations that protect against race actually dominating in redistricting.

And that has been the case for some 40 years.

Section 2 claims, he pointed out, are extremely hard to win in federal courts, and they haven't been winning.

So, he's saying that there are safeguards here, but he is aware that they're dealing with race.

GEOFF BENNETT: And, David, this ruling was seen as a surprise, given, one, the conservative makeup of this court, and, two, the ways in which the court, as we mentioned, in previous rulings has really hollowed out the Voting Rights Act.

The NAACP Legal Defense Fund, an attorney with that organization, argued the case before the court.

And in a statement today: "The organization said this decision is a clear message to lawmakers that their responsibility has not changed.

They must ensure that voters of color are not denied an opportunity to participate in the electoral process."

Is that how you see it?

What are your takeaways from this ruling?

DAVID WASSERMAN, The Cook Political Report: I am somewhat surprised.

I can't say I'm shocked, because the initial decision by the federal court panel to strike down Alabama's congressional map was handed down by two Trump appointees on that panel.

But, look, at once, this is an application of longtime precedent, but it's also a sea change politically, because Alabama's only had one Black-majority district since 1992.

And it was only in the last decade that Black Democratic politicians and other Democrats began to question this kind of configuration of districts.

Now we're likely to see additional or proportional maps enacted in Louisiana as well.

There will be cases that play out in Georgia, potentially South Carolina, Texas, that could net Democrats an additional two to four seats in the House.

And that could put them in closer contention for House control, given how narrow Republicans' margin is today.

GEOFF BENNETT: Well, let's talk more about that, because we have a map that shows the number of states where their congressional districts are now being litigated.

And this decision is going to force many of these states, it will force every state, really, to think about how they redraw congressional lines in areas that have a significant Black population.

Is that right?

DAVID WASSERMAN: Well, not just Black voters, but Hispanic voters in some cases as well.

Keep in mind that Republicans thought they had a bit of an insurance policy heading into 2024 in the House, because they captured control of the North Carolina Supreme Court, which has cleared the path for the Republican legislature there to re-gerrymander the state's boundaries in a way that could net Republicans an additional three seats.

This ruling offsets that, and it could actually impact Republicans' thinking in North Carolina and make them more risk-averse to a -- the threat of a Voting Rights Act lawsuit.

And that could force them to draw a less ambitious plan.

At the same time, New York Democrats believe that the judiciary in that state has turned in their favor.

And some of them are pushing to redraw the state's political boundaries in a way that's advantageous to Democrats.

We could see a net benefit in redistricting for Democrats prior to the 2024 election.

And that's quite different from what we thought would be the case a couple months ago.

GEOFF BENNETT: Marcia, looking at this ruling, what should we see as the significance, if at all, of Chief Justice John Roberts and Brett Kavanaugh siding with the liberals?

MARCIA COYLE: I wasn't surprised the chief justice ended up in the majority or even that he wrote it, because he has been out front on all of the court's major race-related decisions, not just the redistricting context.

Justice Kavanaugh, he hedged a bit in that stay decision last year, so we weren't really sure where he would come out.

But I think the chief justice's ability to put together majorities in closely contested cases really does seem to hinge more and more on whether Justice Kavanaugh will join him in taking either a more restrained opinion than the other conservatives in the majority or just to join with the court's three liberal justices.

So, it's that sort of plan perhaps for the future that Kavanaugh becomes the median justice and the key to whether Roberts can get what he wants when faced with five conservatives who may not want to go along with him.

GEOFF BENNETT: Marcia Coyle and David Wasserman, our thanks to you both.

DAVID WASSERMAN: Thanks.

MARCIA COYLE: You're welcome.