This section applies only in St. Mary’s County. The State’s Attorney’s salary is equal to the salary of a circuit court judge and shall be paid biweekly. A salary increase shall take effect at the beginning of the elected term of office and may not increase during the term of office. The county commissioners shall provide for the administrative support staff, independent office facilities, office equipment, supplies, books, and other items necessary for the operation of the office. The State’s Attorney shall present vouchers to the county commissioners for the payment of office expenses. The State’s Attorney may appoint one deputy State’s Attorney and two or more assistant State’s Attorneys who: shall serve at the pleasure of the State’s Attorney; and may be full–time or part–time employees. The State’s Attorney shall pay the salaries of the deputy and assistant State’s Attorneys biweekly from money that the county commissioners appropriate each year. The State’s Attorney may appoint: administrative staff necessary for the operation of the office; and one or more full–time or part–time investigators as employees. The staff appointed under paragraph (1) of this subsection shall be in the county merit system. The State’s Attorney shall pay the salaries of the investigators appointed under paragraph (1)(ii) of this subsection biweekly from money that the county commissioners appropriate each year. The State’s Attorney may not: engage in the private practice of law; and except in connection with performing the duties of the office, appear professionally in a criminal proceeding in the State.