REDWOOD CITY, Calif. (AP) - A once-prominent Northern California child psychiatrist is set to be retried on charges that he molested patients.

A San Mateo County judge ruled on Wednesday that 80-year-old William Ayres had manipulated mental health experts to avoid prosecution. He set a March 2013 trial date.

Ayres was tried in 2009 on charges that he molested several young boys under his care, but a jury couldn't reach a verdict. He was accused of using physical exams as a cover for the abuse.

Prosecutors attempted to retry him, but Ayres was ruled incompetent and sent to a mental health facility.

San Mateo County Judge John Grandsaert said a key factor in his ruling Wednesday was a report from a psychologist who said Ayres faked or at least exaggerated dementia.

Ayres' attorney, Jonathan McDougall, says he'll consider appealing.

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