LOS ANGELES—The union representing Los Angeles County sheriff’s deputies has filed a second legal action in its dispute with the Board of Supervisors concerning who has legal authority to suspend or fire deputies for noncompliance with the county’s mandatory coronavirus vaccination order. The Association for Los Angeles Deputy Sheriffs originally sued Los Angeles County on Dec. 3 regarding the board’s establishment last August of a mandatory vaccination policy requiring all county workers, including those employed by the sheriff’s department, to be fully vaccinated. The board maintains it has the legal authority to subject those failing to comply to disciplinary action, including being fired. But according to the union’s Los Angeles Superior Court suit, that disciplinary power rests exclusively with Sheriff Alex Villanueva, who has said he will not enforce the county’s mandate due to the adverse impact on his ability to ensure public safety. The first suit is still pending …