Mary Hayashi returned to work Tuesday as the chair of the Business and Professions Committee.
A shoplifting charge against her was dropped from a felony to a misdemeanor after Hayashi offered the brain tumor defense.
But now a University of California, Davis neurology professor says Hayashi's tumor would have required surgery and could not have been treated with medication, as she claims.
Hayashi was arrested in October after walking out of a Neiman Marcus store in San Francisco with a pair of leather pants, black skirt and white blouse worth almost $2,500.
Meantime, Assembly Speaker John Perez was asked Tuesday about Hayashi's ability to serve.
"Her doctors have cleared her, so we have no concerns about that," said Perez.