Employees who suffer from mental illnesses shouldn’t be treated any differently than other employees unless there is a very good reason.
That means not assuming that the employee can’t function or treating him as if he were a child in need of supervision. Instead, let the employee approach you for help with accommodations. Otherwise, assume all is well.
Recent case: Thomas Rice took medical leave for treatment of bipolar disorder. When he returned, he claimed his employer treated him differently. For example, he said his supervisors believed he was a suicide risk and wouldn’t allow him to work with his office door closed. They forced him to have a psychiatric exam.
He sued, alleging disability discrimination, and the court said the case could go to trial. (Rice v. Wayne Behavioral Health Network, No. 09-CV-639, WD NY, 2010)