(a) Persons to be joined if feasible. A person who is subject to service of process shall be joined as a party in the action if (1) in the person's absence complete relief cannot be accorded among those already parties, or (2) the person claims an interest relating to the subject of the action and is so situated that the disposition of the action in the person's absence may (A) as a practical matter impair or impede the person's ability to protect that interest or (B) leave any of the persons already parties subject to a substantial risk of incurring double, multiple, or otherwise inconsistent obligations by reason of the claimed interest. If the person has not been so joined, the court shall order that the person be made a party. If the person should join as a plaintiff but refuses to do so, the person may be made a defendant, or, in a proper case, an involuntary plaintiff.
Rule 19.Joinder of Persons Needed for Just Adjudication.
Last amended January 1, 2000 · Last verified July 3, 2026
In one sentenceRule 19 requires a person to be joined as a party when their absence would prevent complete relief or put them or others at risk, and tells the court how to decide whether a case can go forward when such a person can't be joined.
Full Text of Rule 19
(b) Determination by court whenever joinder not feasible. If a person as described in subdivision (a)(1)-(2) hereof 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, the absent person being thus regarded as indispensable. The factors to be considered by the court include: first, to what extent a judgment rendered in the person's absence might be prejudicial to the person or those already parties; second, 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; third, whether a judgment rendered in the person's absence will be adequate; fourth, whether the plaintiff will have an adequate remedy if the action is dismissed for nonjoinder.
(c) Pleading reasons for nonjoinder. A pleading asserting a claim for relief shall state the names, if known to the pleader, of any persons as described in subdivision (a) (1)-(2) hereof who are not joined, and the reasons why they are not joined.
Amendment History
Amended May 15, 1972, effective July 1, 1972
further amended December 7, 1999, effective January 1, 2000
Plain-English Summary
Rule 19(a) requires a person subject to service of process to be joined as a party when complete relief can't be given among the existing parties without them, or when the person claims an interest in the case that their absence would impair or that would expose an existing party to a substantial risk of double or inconsistent obligations. If such a person hasn't been joined, the court must order them added; a person who should be a plaintiff but refuses can instead be made a defendant, or, in a proper case, an involuntary plaintiff.
When a necessary person can't be made a party, Rule 19(b) has the court weigh, in equity and good conscience, whether to proceed without them or dismiss the case, treating the absent person as indispensable if the case can't proceed on fair terms. The court considers how much a judgment might prejudice the absent person or the existing parties, whether that prejudice can be lessened through protective measures, whether a judgment reached without the absent person would be adequate, and whether the plaintiff would have an adequate remedy if the case were dismissed. A pleading must name any such person not joined and explain why, and the whole rule gives way to Rule 23's class-action provisions.
Frequently Asked Questions
When must a person be joined as a party under Rule 19?
When complete relief can't be given among the parties already in the case without that person, or when the person claims an interest that their absence would impair or that would leave an existing party facing a substantial risk of inconsistent obligations.
What happens when a necessary person can't be joined?
Rule 19(b) has the court decide, in equity and good conscience, whether the action should proceed without that person or be dismissed, treating the person as indispensable if it can't proceed on fair terms.
Does Rule 19 apply to class actions?
No. Rule 19(d) makes the rule subject to Rule 23, which governs joinder in the class-action context instead.
Source & verification. The rule text and History are reproduced verbatim from the
official Hawaii Rules of Civil Procedure (Haw. R. Civ. P. 19). Prescribed by the Supreme Court of Hawaii (Haw. Rev. Stat. § 602-11; Haw. Const. art. VI, § 7). The plain-English summary is original and written by us. Last verified July 3, 2026. ·
Official source
Also known as: indispensable partynecessary party joinderjoinder of persons needed