The statistic was startling and dramatic: In the 102 cases during the past 20 years in which the California Supreme Court reviewed a claim that prosecutors struck prospective jurors on the basis of their race, that court found error only once—and that was 12 years ago.

That “improbable record,” California Supreme Court Justice Goodwin Liu has observed, was attributable, at least in part, to his court’s “erroneous legal framework” for evaluating so-called Batson claims, named after the U.S. Supreme Court’s landmark 1986 decision in Batson v. Kentucky. In Batson, the high court held that striking prospective jurors on the basis of race violated the equal protection clause.