Section 620.50. Material witness order; hearing, determination and execution of order

1.  The hearing upon the application must be conducted as follows:
    (a)  The applicant has the burden of proving by a preponderance of the
  evidence all facts essential to support a material  witness  order,  and
  any testimony so adduced must be given under oath;
    (b)    The  prospective  witness may testify under oath or may make an
  unsworn statement;
    (c)  The prospective witness may call witnesses in his behalf, and the
  court must cause process to be issued  for  any  such  witness  whom  he
  reasonably  wishes  to  call, and any testimony so adduced must be given
  under oath;
    (d)   Upon the hearing,  evidence  tending  to  demonstrate  that  the
  prospective witness does or does not possess information material to the
  criminal  action  in  issue,  or that he will or will not be amenable or
  respond to a subpoena at the time his  attendance  will  be  sought,  is
  admissible even though it consists of hearsay.
    2.    If  the  court  is  satisfied  after  such hearing that there is
  reasonable cause to believe that the prospective witness  (a)  possesses
  information  material  to the pending action or proceeding, and (b) will
  not be amenable or respond to a subpoena at a time when  his  attendance
  will  be  sought, it may issue a material witness order, adjudging him a
  material witness and fixing bail to secure his future attendance.
    3.  A material witness order must be executed as follows:
    (a)  If the bail is posted and approved  by  the  court,  the  witness
  must,  as  provided  in subdivision three of section 510.40, be released
  and be permitted to remain at liberty; provided that, where the bail  is
  posted  by  a  person  other  than the witness himself, he may not be so
  released except upon his signed written consent thereto;
    (b)  If the bail is not posted, or if though posted it is not approved
  by the court, the witness must, as  provided  in  subdivision  three  of
  section 510.40, be committed to the custody of the sheriff.