It is the public policy of the state of Minnesota that every public employee should be provided with the right of independent review, by a disinterested person or agency, of any grievance arising out of the interpretation of or adherence to terms and conditions of employment. When such review is not provided under statutory, charter, or ordinance provisions for a civil service or merit system, the governmental agency may provide for such review consistent with the provisions of law or charter. If no other procedure exists for the independent review of such grievances, the employee may present the grievance to the commissioner under procedures established by the commissioner.