Rule 24.Intervention.

Rule 24(a) gives a timely applicant an absolute right to intervene when a statute confers an unconditional right to do so, or when the applicant claims an interest in the property or transaction at the center of the case and disposing of the action might, as a practical matter, impair the applicant’s ability to protect that interest — unless the existing parties already represent it adequately.

Rule 24(b) lets the court permit intervention on a timely application when a statute confers a conditional right, or when the applicant’s claim or defense shares a question of law or fact with the main action. A government officer or agency administering a statute, executive order, regulation, or agreement that a party relies on may likewise be permitted to intervene on that same common-question basis. In deciding whether to allow permissive intervention, the court weighs whether it will unduly delay or prejudice the rights of the parties already in the case.

Rule 24(c) requires anyone wanting to intervene to serve a motion on all affected parties, stating the grounds and attaching the pleading — a complaint or an answer — that sets out the claim or defense being asserted. A statute granting a right to intervene generally follows this same procedure unless it sets its own. North Carolina’s presiding legislative officers get a shortcut: the Speaker of the House of Representatives and the President Pro Tempore of the Senate may intervene as of right by filing a notice of intervention in whatever court the matter is pending, regardless of the stage the case has reached.