Whenever a vacancy occurs in the position, whether by expiration of the term of office or otherwise, the presiding justice of the superior court, with the concurrence of a majority of the justices of the court, shall have the power to appoint a jury commissioner who shall be a qualified elector of the state, and who shall serve at the pleasure of the presiding justice and a majority of the justices of the superior court. The jury commissioner’s salary shall be determined and set by the unclassified pay plan board and he or she shall be entitled to the same longevity salary increases as though he or she was in the classified service.