A federal appeals court rejected a conservative organization’s challenge Wednesday to the California Voting Rights Act, a law that seeks to further minority representation by requiring a substantial number of local governments and public agencies to switch from at-large to district elections.

The 2002 law requires local governments, school boards and other agencies that hold at-large elections, drawing candidates from their entire area, to change to districts if a local minority group can show that the system is racially polarized. That requires proof that a majority group has historically voted as a bloc to elect its own candidates or pass race-based ballot measures opposed by minorities.

The law has been used in recent years to redraw many local election maps, particularly in school districts, sometimes resulting in the first elections of Latino or other minority candidates to governing boards in decades. San Francisco switched from at-large to district elections under a local ballot measure that took effect in 2000.

Supporters of the law say at-large elections allow a majority, whether racial or political, to ignore minority concerns. Defenders of at-large elections say they encourage candidates to consider the diverse views of an entire community.

Wednesday’s ruling came in a lawsuit by Don Higginson, former mayor of the San Diego County community of Poway, which shifted to district elections to avoid a lawsuit under the California law.

Higginson is represented by the nonprofit Project on Fair Representation, which also sponsored the suit that led to a U.S. Supreme Court ruling in 2013 striking down an important enforcement provision of the U.S. Voting Rights Act. That law had required state and local governments with a history of racial bias to seek Justice Department approval for any changes in their districts or voting rules. But the high court ruled 5-4 that the pervasive discrimination that might have justified the law in the past no longer existed.

Higginson’s lawyers argued that, under Poway’s new election system, he lived in a district that was “racially gerrymandered,” with boundaries that were drawn for racial reasons because of the state law. A federal judge ruled against him in February, and the Ninth U.S. Circuit Court of Appeals in San Francisco upheld that ruling Wednesday.

The suit cited no evidence that Higginson or any other voter was put in a district for racial reasons or that the California law requires race-conscious districts, the court said in a 3-0 ruling.

“Although a finding of racially polarized voting triggers the application of the (California law), it is well settled that governments may adopt measures designed ‘to eliminate racial disparities through race-neutral means,’” the court said.

It quoted language from the Supreme Court’s 2015 ruling upholding a federal ban on housing practices that harmed minorities, regardless of whether the discrimination was intentional. That 5-4 ruling was written by Justice Anthony Kennedy, now retired and replaced by President Trump’s appointee, Justice Brett Kavanaugh.

The California case will be appealed further and could also reach the Supreme Court, said Edward Blum, president of the Project on Fair Representation.

“We believe the California Voting Rights Act is an unconstitutional statute that has the polarizing effect of separating neighbors from one another on the basis of race and ethnicity,” Blum said.

Attorney Julia Gomez of the Mexican American Legal Defense and Educational Fund, which filed arguments in support of the state law, said she was confident that it would be found constitutional.

Where communities vote at large and voting is racially polarized, she said, “you might have a 20% or 25% Latino population, but they can’t even elect one person to the (city) council because for every seat, the majority is outvoting them. ... They essentially have no voice.”

Bob Egelko is a San Francisco Chronicle staff writer. Email: begelko@sfchronicle.com Twitter: @BobEgelko