The U.S. Supreme Court announced Friday that it will hear another case challenging the constitutionality of the Voting Rights Act of 1965, a key measure of the Civil Rights Movement that has been used to defend the rights of minority voters as recently as the last election cycle.

The Supreme Court has agreed to hear the case Shelby County v. Holder, an Alabama case that claims states and municipalities with special restrictions under Section 5 of the Voting Rights Act have made sufficient progress and should no longer be required to comply with these restrictions. Section 5 requires states and municipalities that have a history of discrimination to have any changes to their voting laws approved by the U.S. Justice Department or certain federal courts, but has been using the same formula to determine which areas should receive these restrictions since 1965.

Since 1965, Congress has not changed the list of jurisdictions covered by Section 5.

Section 5 of the act, set in 1965 and originally scheduled to expire in 1970, has been reauthorized four times by Congress. It is set to expire next in 2031.

Nine states, Alabama, Alaska, Arizona, Georgia, Louisiana, Mississippi, South Carolina, Texas and Virginia, and other municipalities are affected by the Section 5 restrictions. The act has been applied recently by the Justice Department in Texas to block the passage of voter ID laws and to challenge redistricting.

The Supreme Court last declared Section 5 constitutional in 1966.