In any case in which the court has sent a notification to the Attorney General of the United States or the Attorney General of the District of Columbia under Rule 5.1, the court must permit the United States or the District of Columbia, respectively, to intervene for the presentation of evidence, if evidence is otherwise admissible in the case, and for argument on the question of constitutionality. The United States, or the District of Columbia, as appropriate, must, subject to the applicable provisions of law, have all the rights of a party and be subject to all liabilities of a party as to court costs to the extent necessary for a proper presentation of the facts and law relating to the question of constitutionality.
Rule 5.1-I.Intervention by the United States or the District of Columbia
Group II: Commencing an Action; Service of Process, Pleadings, Motions, and Orders · Last amended 2017 · Last verified July 14, 2026
In one sentenceRule 5.1-I requires the court to let the United States or the District of Columbia intervene, once notified under Rule 5.1, to present evidence and argue the constitutional question, and gives the intervenor the same rights and cost liabilities as any other party for that purpose.
Full Text of Rule 5.1-I
Comment
Stylistic changes were made to this rule to conform with the 2007 amendments to the Federal Rules of Civil Procedure. This rule was also renumbered to correspond with the relocation to Rule 5.1 of provisions related to notice, certification, and intervention by the United States or the District of Columbia when there is a constitutional challenge.
Plain-English Summary
Rule 5.1 tells a party when to notify the government that a law's constitutionality is in question and requires the court to certify that notice. Rule 5.1-I supplies the other half: once the court has sent that notification to the United States Attorney General or the District of Columbia Attorney General, the court must permit the United States or the District of Columbia, whichever was notified, to step into the case for the limited purpose of the constitutional question.
That right to intervene covers presenting evidence — so long as the evidence would otherwise be admissible in the case — and arguing the constitutionality issue itself. To make that participation workable, the rule gives the intervenor all the rights of a party and subjects it to all the liabilities of a party as to court costs, to the extent needed for a proper presentation of the facts and law bearing on constitutionality. The intervenor is not folded into the whole case; its participation is tied to the constitutional question that brought it in.
Frequently Asked Questions
Does the court have discretion to deny the government's request to intervene under this rule?
No. Once the court has sent the notification required by Rule 5.1 to the United States or the District of Columbia, Rule 5.1-I requires the court to permit that government to intervene for presenting evidence and arguing the constitutional question.
What can the intervening government do in the case?
It may present evidence, if that evidence would otherwise be admissible, and argue the question of constitutionality. Its participation is tied to that constitutional issue rather than to the rest of the underlying dispute.
Does the intervening government have to pay court costs like any other party?
Yes, to the extent necessary for a proper presentation of the facts and law relating to the constitutional question. Rule 5.1-I gives the intervenor the rights of a party and subjects it to a party's liabilities for costs.
Is Rule 5.1-I intervention the same as intervention under Rule 24?
Can a private party object to the government's intervention under this rule?
The rule itself states the court must permit the intervention once notification has gone out under Rule 5.1; it does not condition that right on the other parties' consent.
Source & verification. Rule text and official Comments are
reproduced verbatim from the District of Columbia Superior Court Rules of Civil
Procedure, adopted by the Superior Court of the District of Columbia. Last verified July 14, 2026.
· Official source
Also known as: dc rule 5.1-i interventionunited states intervene constitutional challenge dcdistrict of columbia intervenes in civil casedc attorney general party status costs