A state appellate court has ruled that Tucson Unified School District has legal immunity from a lawsuit accusing it of negligently hiring a teaching assistant later convicted of attempting to secretly record a special-needs student.

The Court of Appeals ruled that the district had immunity from the suit by the student's parents because the principal who hired Michael H. Corum didn't know he'd been fired from a previous job after he inappropriately touched a patient.

The Court of Appeals said state law gives public entities in Arizona immunity for things done or not done by public employees unless the public entity knew the employee had a tendency for that action.

The court's ruling issued Tuesday also said there's no evidence the district had that knowledge.