It took 25 years to remedy the prosecutorial misconduct that tainted Crossan Hoover's murder conviction. Hoover was convicted of beating a man to death when he was 17, at the direction of his employer, who hoped to turn Marin County "into King Arthur's court, with himself as king and teens as knights."

He might have been found insane if jurors had been given proper instructions and if the prosecutor had not withheld key information from a psychiatric witness, U.S. Magistrate James Larson said in a Sept. 7 ruling.

A court-appointed psychiatrist testified that Hoover was motivated by money, not by mental illness. But prosecutors didn't give the psychiatrist the facts he needed to make an informed judgment.

The psychiatrist, John Buehler, has since said his assessment of Hoover would have been different if he had known that information. "The prosecutor's manipulation of the evidence provided to his expert, Dr. Buehler, so distorted the expert's testimony as to amount to false evidence," Larson said.

If prosecutors decide to bring Hoover to trial again, perhaps this time they'll play by the rules.