(a) Designation of parties
In cases filed under the Family Code, use the following designations for parties.
(1) Except as otherwise specified in this rule, the party starting the case is referred to as the “petitioner,” and the other party is the “respondent.”
(2) If the parties initiate the case by joint petition under Family Code sections 2330 and 2331 or section 2400:
(A) The first joint petitioner is referred to as “petitioner 1,” and the second joint petitioner is referred to as “petitioner 2.” For any Judicial Council forms that list the parties as “petitioner” and “respondent,” petitioner 1 should identify themselves as “petitioner” and petitioner 2 should identify themselves as “respondent.”
(B) If either party revokes the joint petition under Family Code section 2342.5(b), petitioner 1 will thereafter be referred to as the “petitioner” and petitioner 2 will thereafter be referred to as the “respondent.
(3) In local child support agency actions, the local child support agency starts the case and is the petitioner or plaintiff in the case. The parent sued by the child support agency is the “respondent” or “defendant,” and the parent who is not the defendant is referred to as the “Other Parent.” Every other proceeding must be prosecuted and defended in the names of the real parties in interest.
(Subd (a) amended effective January 1, 2026.).
(b) Parties to proceeding
(1) The only persons permitted to be parties to a proceeding for dissolution, legal separation, or nullity of marriage are the spouses, except as provided in (3), a third party who is joined in the case under rule 5.24, or a local child support agency that intervenes in the case.
(2) The only persons permitted to be parties to a proceeding for dissolution, legal separation, or nullity of domestic partnership are the domestic partners, except as provided in (3), a third party who is joined in the case under rule 5.24, or a local child support agency that intervenes in the case.
(3) In a nullity proceeding, the case can be started by the spouses or domestic partners. The case may also be started by a parent or guardian, conservator, or other person specified in Family Code section 2211. For this type of case, the person starting the case is a party and the caption on all papers must be appropriately changed to reflect that fact.
(4) The only persons permitted to be parties to a proceeding under the Domestic Violence Prevention Act are those identified in Family Code section 6211.
(5) The only persons permitted to be parties to a family law proceeding to establish parentage are the presumed or putative parents of the minor child, the minor child, a third party who is joined in the case under rule 5.24, or a local child support agency that intervenes in the case.
Rule 5.16 amended effective January 1, 2026; adopted January 1, 2013.