The Supreme Court this week decided Town of Chester v. Laroe Estates, in which a unanimous court ruled that an intervenor in federal court proceedings must show independent standing under Article III of the Constitution: namely that they have personally suffered some actual or threatened injury that can be directly traced to the action of the defendant, and that the injury would likely be redressed by a favorable decision.

In this Q&A, Associate Professor of Law Shirin Sinnar, who teaches courses in civil procedure, discusses the recent decision.

What is the significance of the decision?

The decision may make it harder for parties that aren’t originally part of a lawsuit to participate in litigation, for better or for worse.  Many cases affect people who aren’t part of the original lawsuit, and intervention provides a means for them to get involved to protect their interests.  Sometimes this is in private disputes, as in the case before the Supreme Court, where the intervenor was a real estate developer with a financial stake in another developer’s dispute with the city.  But it often occurs in public

law contexts, where the outcome of the case may affect a lot of people beyond the original parties.  This can be a good thing, in that it increases the information and perspectives available to the court, but it can also make the litigation more costly and burdensome, since intervening parties generally have the same rights to assert claims, demand discovery, and make motions as original parties.

To take a recent high-profile example of intervention where standing proved an issue, California proponents of Prop. 8 – the ballot measure banning same-sex marriage – intervened in the constitutional challenge to the measure after the state of California refused to defend the initiative.  Eventually, the Supreme Court dismissed their appeal of a lower court decision invalidating Prop. 8 because it found they lacked standing.  The decision in Town of Chester v. Laroe Estates goes further in requiring standing for an intervenor not just to appeal a decision, but to ask for any additional relief beyond that which other parties with standing are seeking.

How does this decision break from rules governing intervenor standing in the recent past?

The courts of appeal had been split for many years on whether an intervening party needed independent standing in a case where an existing plaintiff did have standing.  The Supreme Court had previously dodged the question.  This decision sides with the circuits that had ruled that an intervenor-of-right does require standing, but it limits that requirement to scenarios in which the intervening party is seeking “different” or “additional” relief from that sought by other plaintiffs.

What does it mean?  How does this impact access to justice for intervenors, positively or negatively?

The decision means that intervening parties seeking damages in their own right, or a different injunction from that sought by the plaintiffs, must satisfy Article III standing requirements.  In many cases, the new rule will not present much of a burden because, to satisfy the existing procedural rules for intervening by right, litigants already have to show that they have an interest at stake that will be impaired if they are not able to participate in the case.  The decision may have particular impact where intervenors are seeking declaratory or injunctive relief, such as cases where a public interest organization that has intervened in a case on behalf of an affected community is seeking broader relief from that sought by other parties.

Are there limits to the decision?

Even with this decision, intervening parties that lack standing have a lot of power to affect ongoing litigation, so long as they’re not seeking different relief; for instance, they can still file their own motions, ask for additional discovery, or present legal arguments different from those made by other parties.  The decision also says nothing about a second category of intervenors who ask for permission to intervene, usually for a limited purpose, and often subject to substantial court-designated limits on their participation.  A media organization intervening in a case solely to unseal a court document, for instance, may not be affected by this decision.

Shirin Sinnar is an associate professor at Stanford Law School.