The California Supreme Court has proved that sometimes even a C can put you at the top of the class.

In a study released Wednesday, California's high court ranked first in the nation in the way state supreme courts handle financial disclosure and conflict-of-interest rules for individual justices, earning a C as 43 states received an F for failing to take adequate steps to avoid financial conflicts.

California's Supreme Court received particularly high marks for making financial information readily available to the public, the result of a move last year by the state's Fair Political Practices Commission to require all of the state's judges to post their financial information online. Some judges around the state had opposed the requirement, but it helped separate California from other less open states.

The state Supreme Court did have some stumbles in the analysis conducted by the Washington, D.C.-based Center for Public Integrity. In one instance last year, Justice Kathryn Mickle Werdegar, one of the court's senior members, voted against taking a case against Wells Fargo Bank when she should have recused herself because she held between $100,000 and $1 million in Wells Fargo stock.

A state Supreme Court spokesman said the court's internal financial conflicts list mistakenly did not include Werdegar's own Wells Fargo holdings and that she should have disqualified herself. Werdegar, through the spokesman, said she "regrets the error," and the Supreme Court indicated it is re-evaluating its procedures to avoid a similar misstep.

California's high court has generally avoided the experience of many other states where justices have been accused of conflicts of interest, partly because most California Supreme Court elections are free of political influence. Unlike many states, California Supreme Court justices do not run opposed by other candidates (they are subject to retention elections for 12-year terms), and the justices run in nonpartisan races, diminishing the amount of political money justices must raise from donors.

California also has strict rules to keep Supreme Court justices from participating in cases in which they may have a financial stake. And experts say that is important for the public perception of the court's business.

"California is definitely ahead in that regard," said Ann Ravel, recently departed head of the state's Fair Political Practices Commission. "There is nothing more important than having a judge hearing your case being impartial."

Howard Mintz covers legal affairs. Contact him at 408-286-0236, or follow him at Twitter.com/hmintz.