Each justice of the supreme court may employ a law clerk who is a graduate of a law school which meets the standards of accreditation of the American Bar Association. Each law clerk shall serve at the pleasure of the justice who selected him. Supreme court law clerks shall:
A. perform duties as provided by rule of the supreme court;
B. not engage in the private practice of law; and
C. not receive any additional salaries because of the services rendered to the state.