Mich. Comp. Laws § 37.273

Sec. 3. An employer shall not do any of the following: (a) Request an employee or an applicant for employment to grant access to, allow observation of, or disclose information that allows access to or observation of the employee's or applicant's personal internet account. (b) Discharge, discipline, fail to hire, or otherwise penalize an employee or applicant for employment for failure to grant access to, allow observation of, or disclose information that allows access to or observation of the employee's or applicant's personal internet account.