[3] This was known as the preclearance requirement and affected mostly southern states, making them seek approval from the U.S. District Court for any changes to their voter registration and voting system.

The court intentionally heard the case prior to June of 1966 so their decision would be in effect for South Carolina's primary elections that year.

In his opinion for the Court, Chief Justice Earl Warren wrote that the Voting Rights Act of 1965 was a valid exercise of Congress' power under the enforcement clause of the Fifteenth Amendment to the United States Constitution.

Warren cited the enforcement clause of the 15th Amendment which gave Congress full powers to stop discrimination in regards to voting.

The only dissent in the ruling came from Justice Hugo L. Black who opposed the legislation because he felt it exceeded the textual reach of the constitution.

According to Indiana University Maurer School of Law professor Luis Fuentes-Rohwer, the case served as an example of a firm interpretation of the 15th Amendment, which granted Congress "full remedial powers" to prevent any racial discrimination.

The Supreme Court struck down provisions in the Voting Rights Act 5-4 because it was based on decades-old data, making it no longer applicable to present laws and regulations.