Which statement describes supplemental jurisdiction appropriately?

• A. Supplemental jurisdiction allows federal courts to hear any related state claim regardless of federal jurisdiction.
• B. Supplemental jurisdiction exists only when there is an underlying claim within federal jurisdiction that shares a common nucleus of operative fact.
• C. Supplemental jurisdiction always applies in diversity cases with multiple parties.
• D. Supplemental jurisdiction requires removal to federal court first, then state court can hear the remaining claims.

Answer: (B)

Supplemental jurisdiction lets a federal court hear state-law claims that are part of the same case or controversy as a federal claim, but only if there is an original basis of federal jurisdiction for at least one claim and the related state claims share a common nucleus of operative fact with that federal claim. This ensures the federal court can wisely resolve all related issues in one proceeding without turning into a jury of separate proceedings for different laws.

The statement describing this correctly says there is an underlying federal-jurisdiction claim and the state claims share a common nucleus of operative fact. That captures the essential condition: you must have a component of the case already within federal jurisdiction, and the remaining claims must be tightly tied to the same facts that gave rise to the federal claim.

The other statements go too far or misstate the process. It’s not enough to have related state claims simply because they are related; there must be an original federal basis for jurisdiction. Supplemental jurisdiction is not automatic in every diversity case or any case with multiple parties. And you don’t need, nor do you perform, a step where you remove to federal court and then the state court reclaims jurisdiction for the remaining claims—the relationship is that the federal court itself handles the related state-law claims when there is proper federal jurisdiction to begin with.