607A.29  Length of service.
  In any two-year period, a person shall not be required:
  1.  To serve or attend court for prospective juror service for more than a term of service ordered by the court, not to exceed three months, unless necessary to complete service in a particular case.
  2.  To serve on more than one grand jury.
  3.  To serve or attend as both a grand and a petit juror.
86 Acts, ch 1108, §37