Unlike state courts, federal courts are courts of limited jurisdiction. Federal courts have “original jurisdiction” over claims alleging a federal question or diversity jurisdiction. To bring a claim in federal court, the complaint must either allege (1) a federal question, i.e. a question “arising under the Constitution, laws, or treaties of the United States,” see 28 U.S.C. § 1331; or (2) diversity of citizenship, meaning that the parties are citizens of different states, and the amount in controversy exceeds the sum or value of $75,000, see 28 U.S.C. § 1332.
Federal courts also have discretion to exercise supplemental jurisdiction. 28 U.S.C. § 1367(a) directs that, “in 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.” This supplemental jurisdiction “shall include claims that involve the joinder or intervention of additional parties.” Id.
- the claim raises a novel or complex issue of state law,
- the claim substantially predominates over the claim or claims over which the district court has original jurisdiction,
- the district court has dismissed all claims over which it has original jurisdiction, or
- in exceptional circumstances, there are other compelling reasons for declining jurisdiction.
28 U.S.C. § 1367(c).