The term of a commissioner is four years. A commissioner holds office until a successor is appointed and qualified, but the successor’s term expires four years from the legal date of expiration of the term of the successor’s predecessor. A commissioner may be removed from office by the governor upon charges and after a hearing. The term of a commissioner who ceases to hold the qualifications required ends and a successor may be appointed. Vacancies occurring in the office of a commissioner from any reason or cause shall be filled for the unexpired term in the same manner as for a full term appointment.