Supplemental Jurisdiction
28 U.S.C. §1367 - Supplemental jurisdiction
(a) “[I]n any civil action of which the district courts have original jurisdiction, the district courts shall have supplemental jurisdiction over all other claims that are so related to claims in the action within such original jurisdiction that they form part of the same case or controversy under Article III of the United States Constitution. Such supplemental jurisdiction shall include claims that involve the joinder or intervention of additional parties.”
Supplemental Jurisdiction Test:
If a federal claim is substantive, and state and federal claims derive from a common nucleus of operative fact, then the state claims can be heard alongside the federal claims in federal court.
Gibbs Discretionary Factors:
[1] The federal claim drops out early.
[2] State issues predominate the case.
[3] The state law issues are novel or complex.
[4] Trying the state and federal law claims together is likely to create jury confusion.
Amended Complaint Rule:
When a plaintiff amends their complaint to remove the federal law claims that enabled removal to federal court, leaving only state law claims behind, the federal court loses supplemental jurisdiction over the state claims, and the case must be remanded to state court.
• Royal Canin U.S.A., Inc. v. Wullschleger, 604 U.S. _ (2025)