Of the Parties to Civil ActionsCompulsory Joinder

Section § 389

Explanation

This law explains what to do if there's someone who should be part of a lawsuit because their involvement is necessary to give everyone complete relief, or because not having them could cause problems for them or others involved in the case. It lays out the rules for including such a person in the lawsuit to avoid issues like double obligations. If the person can't be joined, the court will decide whether to continue without them or dismiss the case. It looks at how not having this person might hurt anyone involved and if the plaintiff can still be appropriately helped. Any complaint should list missing necessary parties and explain why they're not included. Class actions are not affected by this law.

(a)CA Civil Procedure Code § 389(a) A person who is subject to service of process and whose joinder will not deprive the court of jurisdiction over the subject matter of the action shall be joined as a party in the action if (1) in his absence complete relief cannot be accorded among those already parties or (2) he claims an interest relating to the subject of the action and is so situated that the disposition of the action in his absence may (i) as a practical matter impair or impede his ability to protect that interest or (ii) leave any of the persons already parties subject to a substantial risk of incurring double, multiple, or otherwise inconsistent obligations by reason of his claimed interest. If he has not been so joined, the court shall order that he be made a party.
(b)CA Civil Procedure Code § 389(b) If a person as described in paragraph (1) or (2) of subdivision (a) cannot be made a party, the court shall determine whether in equity and good conscience the action should proceed among the parties before it, or should be dismissed without prejudice, the absent person being thus regarded as indispensable. The factors to be considered by the court include: (1) to what extent a judgment rendered in the person’s absence might be prejudicial to him or those already parties; (2) the extent to which, by protective provisions in the judgment, by the shaping of relief, or other measures, the prejudice can be lessened or avoided; (3) whether a judgment rendered in the person’s absence will be adequate; (4) whether the plaintiff or cross-complainant will have an adequate remedy if the action is dismissed for nonjoinder.
(c)CA Civil Procedure Code § 389(c) A complaint or cross-complaint shall state the names, if known to the pleader, of any persons as described in paragraph (1) or (2) of subdivision (a) who are not joined, and the reasons why they are not joined.
(d)CA Civil Procedure Code § 389(d) Nothing in this section affects the law applicable to class actions.
joinder necessary party complete relief ...

Section § 389.5

Explanation

If there is a court case about who owns something or disputes about claims to it, and someone who isn't already in the case has a stake in what happens, they can ask to join in. The court can then decide to officially include them in the case.

When, in an action for the recovery of real or personal property, or to determine conflicting claims thereto, a person not a party to the action but having an interest in the subject thereof makes application to the court to be made a party, it may order him to be brought in by the proper amendment.
recovery of property conflicting claims real property ...