## Facts

- Hanna, an Ohio citizen, brought a diversity tort action in the U.S. District Court for the District of Massachusetts seeking damages for injuries from a South Carolina automobile accident allegedly caused by decedent Louise Plumer Osgood.
- Hanna sued Plumer in his capacity as executor of Osgood’s Massachusetts estate.
- Hanna served process by leaving the summons and complaint with Plumer’s wife at Plumer’s residence, a method permitted by Federal Rule of Civil Procedure 4(d)(1).
- Massachusetts law required “in-hand” service on an executor within one year as a condition for maintaining an action against the estate.
- The district court granted summary judgment for Plumer, treating the state service requirement as controlling in diversity because it was outcome determinative.
- The First Circuit affirmed, reasoning the state requirement was tied to substantive state policy governing estates.
- The Supreme Court granted certiorari.

## Issues

1. In a federal diversity action, when a Federal Rule of Civil Procedure prescribes a method of service that conflicts with a state service requirement, which rule governs?
2. What framework applies when assessing the applicability of a Federal Rule that is “on point” in the face of conflicting state law under Erie and the Rules Enabling Act?

## Decision

- The Supreme Court reversed and remanded.
- Federal Rule of Civil Procedure 4(d)(1) governed service of process in federal court, not the Massachusetts in-hand service requirement for executors.
- When a Federal Rule directly conflicts with state law and is valid under the Rules Enabling Act and the Constitution, the Federal Rule controls in diversity cases.
- The Court rejected a mechanical use of the “outcome-determinative” test; Erie analysis is informed by discouraging forum-shopping and avoiding inequitable administration of the laws.

## Legal Principles

- In diversity cases, federal courts apply state substantive law and federal procedural law; the “outcome-determinative” approach is assessed in light of Erie’s aims of preventing forum-shopping and inequitable administration.
- If a Federal Rule is sufficiently broad to control the issue and directly conflicts with state law, the Federal Rule applies if it is valid under the Rules Enabling Act and consistent with the Constitution.
- The validity of a Federal Rule is not measured by Erie; it is measured by the Rules Enabling Act’s limitation that rules not abridge, enlarge, or modify substantive rights, plus constitutional constraints.
- Rules governing the manner of service regulate procedure (the means of enforcing rights), and a valid federal service rule may displace a stricter state service requirement even if the state rule could bar the action.

## Conclusion

The Court held that, in federal diversity litigation, a valid Federal Rule that directly addresses the disputed procedural question governs over conflicting state law; Erie’s outcome-focused inquiry does not override an on-point Federal Rule that complies with the Rules Enabling Act and constitutional limits.


Hanna v. Plumer, 380 U.S. 460 (1965)