## Facts

- Wilfredo Rodriguez-Diaz, a Puerto Rico native, was seriously injured at age 17 in a motorcycle–automobile collision in Caguas, Puerto Rico.
- He alleged negligence by the automobile driver, Marcelo Sierra-Martinez, and medical malpractice by multiple Puerto Rico medical providers and related entities that treated him after the accident.
- He claimed negligent emergency and follow-up care caused a severe bone infection and worsened a leg injury.
- After treatment in Puerto Rico, he moved to New York, received medical treatment there, and asserted he intended to make New York his permanent home.
- He filed suit in the U.S. District Court for the District of Puerto Rico, asserting diversity jurisdiction on the ground that he was a New York citizen while all defendants were Puerto Rico citizens.

## Issues

1. Whether, for purposes of 28 U.S.C. § 1332, an 18-year-old who relocates from Puerto Rico to New York with intent to remain may acquire a New York domicile despite Puerto Rico law treating persons under 21 as minors whose domicile follows their parents.
2. Whether federal or Puerto Rico law governs a person’s capacity to select a domicile for federal diversity jurisdiction.

## Decision

- The First Circuit reversed the dismissal for lack of subject-matter jurisdiction and remanded.
- The court held that capacity to acquire a domicile for diversity purposes is governed by federal law, not automatically by the age-of-majority rule of the prior jurisdiction.
- It concluded that an 18-year-old may establish an independent domicile for § 1332 if the ordinary domicile elements are met (presence and intent to remain).
- It determined the district court erred by treating the plaintiff as bound to his parents’ Puerto Rico domicile solely because Puerto Rico set majority at 21.

## Legal Principles

- For diversity jurisdiction, “citizenship” turns on domicile, a federal-law concept applied to implement 28 U.S.C. § 1332.
- Domicile requires (1) physical presence in the place claimed and (2) intent to remain there indefinitely.
- A person’s capacity to choose a domicile for diversity purposes is not rigidly controlled by the age-of-majority law of the place of origin when federal jurisdictional policy requires a workable, uniform rule.
- An individual who has reached age 18 may, under federal law, form the intent necessary to establish a new domicile for diversity purposes, even if the former jurisdiction would still treat the person as a minor for local-law purposes.

## Conclusion

The First Circuit held that an 18-year-old who moved to New York and intended to remain there could be deemed domiciled in New York for § 1332 diversity, so the district court improperly dismissed the action by treating Puerto Rico’s age-21 majority rule as controlling on domicile capacity.


Rodriguez-Diaz v. Sierra-Martinez, 853 F.2d 1027 (1st Cir. 1988)