ST. LOUIS (CN) – Ruling against a Missouri school district where black voters routinely see their preferred candidates defeated, the Eighth Circuit affirmed Tuesday that the at-large voting system dilutes minority votes.

Located in north St. Louis County, the Ferguson-Florissant School District serves 11,000 students and was created by a desegregation order in 1975 to remedy the effects of discrimination against black students.

In a district where black students constitute 77 percent of the school population, however, the district saw just one black resident elected to its seven-member school board over the next 40 years.

Such results sparked a federal complaint in 2014, and U.S. District Judge Rodney Sippel agreed two years later the district’s system of at-large voting resulted in violations of the federal Voting Rights Act.

On appeal the district failed to sway the Eighth Circuit that it gave black residents an equal opportunity to elect their preferred candidates to a board that represents the entire district.

Representatives for the American Civil Liberties Union, which brought the suit here on behalf of the Missouri NAACP and three residents, applauded Tuesday’s ruling.

“The courts have ruled yet again that the Ferguson-Florissant school district’s election system illegally dilutes African American voting power,” Julie Ebenstein, senior staff attorney with the ACLU’s Voting Rights Project, said in a statement. “The decision takes another step toward dismantling systematic bias in local elections, and ensuring that all communities’ interests are equally represented.”

Tony Rothert, legal director of the ACLU of Missouri, added: “We presented strong evidence that the election scheme operates to dilute the votes of black voters and today’s ruling vindicates the district court’s careful factual analysis based on complex evidence. We must remain vigilant about the voting rights of the people and continue removing artificial barriers that prevent communities of color from having the same opportunity as white voters to elect candidates that will be responsive to them.”

Cindy Ormbsy, an attorney representing Ferguson-Florissant, said in an email that the school district is weighing its options.

“I am, of course, disappointed in the Eighth Circuit’s ruling issued this morning,” Ormsby wrote. “The Ferguson Florissant Board of Education is meeting in the next few days to discuss all of its options. The District has 14 days to decide whether or not to appeal this ruling.”

The ACLU brought its complaint over Ferguson-Florissant schools the same year that the city of Ferguson was thrust into the national spotlight for a white police officer’s shooting of Michael Brown, an unarmed black teenager.

Brown graduated from Normandy High in a neighboring school district.

Tuesday’s ruling, which U.S. Circuit Judge Jane Kelly wrote for a three-person panel, unraveled a claim that the slight numeric superiority black voters have in the Ferguson-Florissant School District makes it ‘impossible’ for white bloc voting to defeat a black-preferred candidate.

“To the extent this argument is merely a reframing of FFSD’s position concerning the racial makeup of the voting age population in the district, we again find it unpersuasive,” Kelly wrote.