The Supreme Court on Thursday struck down Alabama’s congressional map, a surprise ruling that it likely violates the Voting Rights Act by diluting the power of Black voters.

In a 5-4 decision, the court affirmed a lower ruling that ordered the GOP-led state to create a new map with an additional majority-Black district.

Alabama’s map included one majority-Black district out of the state’s seven total districts, despite accounting for about 27 percent of the state’s population.

It marks a surprising shift for the Supreme Court, which last year signaled skepticism about striking down the map by putting the lower court’s ruling on hold in a 5-4 emergency decision as the justices considered the case more fully.

Chief Justice John Roberts and Justice Brett Kavanaugh joined the court’s three liberals in the majority.

“As we explain below, we find Alabama’s new approach to §2 compelling neither in theory nor in practice. We accordingly decline to recast our §2 case law as Alabama requested,” Roberts wrote for the majority.

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