Rule 3-214.Intervention

Intervention lets someone who isn't already a party step into an ongoing District Court case because it affects them. Rule 3-214(a) creates intervention of right in two situations: when the person has an unconditional right to intervene under some other law, or when the person claims an interest in the property or transaction at the heart of the case, and disposing of the case could as a practical matter impair that interest unless an existing party already protects it adequately.

Section (b) covers permissive intervention, which rests in the court's discretion. Anyone with a claim or defense sharing a common question of law or fact with the case may ask to intervene. The federal government, the State, a political subdivision, or any of their officers or agencies gets a specific path in when the validity of a constitutional provision, charter provision, statute, ordinance, regulation, executive order, requirement, or agreement is drawn into question in the case, or when a party's claim or defense relies on one of those. Whichever type of permissive intervention is at issue, the court weighs whether allowing it would unduly delay or prejudice the rights of the parties already in the case.

Both types of intervention require a timely motion. Section (c) sets the procedure: the person seeking to intervene files and serves a motion stating the grounds, along with a copy of the proposed pleading setting out the claim or defense they want to raise. If the court grants the motion, its order designates the intervenor as a plaintiff or a defendant, and the intervenor must then promptly file that pleading and serve it on everyone else in the case.