(1) An existing child custody determination;
(2) A request to do so from a court in a pending child custody proceeding;
(3) A reasonable belief that a criminal statute has been violated; or
(4) A reasonable belief that the child has been wrongfully removed or retained in violation of the Hague Convention on the Civil Aspects of International Child Abduction.
(b) A prosecutor or appropriate public official acting under this section acts on behalf of the court and may not represent any party.