A federal appeals court overturned Washington state's ban on voting by convicted felons Tuesday in a ruling that could extend ballots to prisoners in other states where studies showed racial bias in the criminal justice system.

In a 2-1 decision, the Ninth U.S. Circuit Court of Appeals in San Francisco said the Washington law violates the federal Voting Rights Act because evidence showed discrimination against minorities at every level of the state's legal system: arrest, bail, prosecution and sentencing.

If the ruling survives, it will be binding in the circuit's other eight states, including California, which denies voting rights to 283,000 convicted felons in prison or on parole, according to a report from the nonprofit Sentencing Project.

About 114,000 are African Americans, who are disenfranchised at seven times the rate of the general population, the report said.

Among those in Washington state who commit crimes, "minorities are more likely than whites to be searched, arrested, detained and ultimately prosecuted," Judge A. Wallace Tashima said in the appeals court's majority opinion.

For example, he said, studies showed that African Americans in Washington were more than nine times as likely to be in prison as whites and 70 percent more likely to be searched, even though a study of one police department found that officers were more likely to find contraband when searching whites.

Findings were similar for Latinos and Native Americans, none of which could be explained by differences in crime rates, Tashima said.

The Voting Rights Act "demands that such racial discrimination not spread to the ballot box," he said.

Dissenting Judge Margaret McKeown said the court should have told a trial judge to reconsider the Washington law based on an amendment last year that made it easier for paroled felons to vote.