The Supreme Court on Tuesday is hearing arguments in an Alabama redistricting case that could further erode the landmark Voting Rights Act, which prohibits discrimination in voting.

Why it matters: It puts on the chopping block a portion of the act that civil rights groups and minority voters have relied on for decades to challenge racially discriminatory redistricting maps.

• The ruling could also carry implications for how other states draw their own congressional maps.

What the Supreme Court is considering in Merrill v. Milligan

• The Supreme Court is weighing Alabama's 2021 congressional redistricting map, drawn by the state's GOP-legislature after the 2020 census.
• The congressional map gave Black voters — about 27% of the state — the majority in just one of the state's seven congressional districts, AP notes.
• The lawsuit filed on behalf of voters argued that the maps violate Section 2 of the Voting Rights Act, which requires that states provide minority voters with "an equal opportunity to participate in the political process," by diluting Black voter strength.
• The state has defended the Republican-drawn map, saying that it is taking a "race neutral" approach to redistricting and it is asking the court to overturn a lower court decision, per AP.

How the Alabama case got to the Supreme Court — and what they're saying

• A three-judge lower court, including two appointees of former President Trump, in January said Alabama's congressional map violated Section 2 of the Voting Rights Act.
• "The appropriate remedy is a congressional redistricting plan that includes either an additional majority-Black congressional district, or an additional district in which Black voters otherwise have an opportunity to elect a representative of their choice," the judges said in a 225-page ruling.
• The state of Alabama asked the Supreme Court to put the lower court hearing on hold while it appealed, which the justices allowed, AP reports.
• The Supreme Court in a 5-4 vote sided with the state, putting on hold the lower court ruling, and allowing the congressional map to stand for the 2022 elections.
• Supreme Court Justice Elena Kagan, with Justices Stephen Breyer and Sonia Sotomayor, dissented from the ruling, writing that “[it] forces Black Alabamians to suffer what under” the Voting Rights Act "is clear vote dilution."

Implications of the court's decision on the Voting Rights Act

• Civil rights groups and minority voters have relied on Section 2 of the Voting Rights Act to dispute racially discriminatory maps, per the liberal-leaning Brennan Center for Justice.
• Parts of the 1965 Voting Rights Act has been weakened by the Supreme Court at least two times over the last decade.

In 2013, the court eliminated a provision of the act that required oversight of any changes to election laws in some states with a history of discrimination in voting, per AP.

• And last year, the court upheld voting laws that critics said made it more difficult to bring cases under Section 2, per AP.
• The most immediate impacts of the Supreme Court's decision in Merrill v. Milligan could be in Georgia and Louisiana, where courts have already found that Section 2 requires redrawing of congressional maps, per the Brennan Center.

Go deeper... Mapped: Voting rights for 2022