Supplemental Jurisdiction

An important issue in American federalism has been the extent to which courts created by the federal government may adjudicate claims that would, standing alone, ordinarily lie outside their subject matter jurisdiction, but that have a relationship to matters already before the federal court.
The Demonstration explores this issue of "supplemental jurisdiction". You can vary: (1) the nature of the underlying jurisdiction-conferring claim; (2) the nature of the potential additional claim; and (3) the applicability of 28 U.S.C. § 1367, so as to appreciate how the enactment of that statute changed existing law.
Your selections yield a graphical illustration and a short description of the outcome. Federal jurisdiction exists over claims depicted with dark green arrows. Supplemental jurisdiction is available over claims depicted with light green arrows. No supplemental jurisdiction is available over claims depicted with red arrows. Yellow arrows denote a situation in which the existence of jurisdiction depends on additional factors.


  • [Snapshot]
  • [Snapshot]
  • [Snapshot]


Snapshot 1: A second plaintiff attempts, before the enactment of 28 U.S.C. § 1367, to add a non-federal claim against a defendant already defending a lawsuit with a claim that has an independent basis for federal jurisdiction.
Snapshot 2: A second plaintiff attempts, after the enactment of 28 U.S.C. § 1367, to add a non-federal claim against a defendant already defending a lawsuit with a claim that has an independent basis for federal jurisdiction.
Snapshot 3: A defendant attempts to bring a non-federal claim against a plaintiff that has sued the defendant on claim with an independent basis for federal jurisdiction.
Unless otherwise noted, the potential additional claims are assumed to be factually related to the underlying claim such that they form part of the same "case or controversy".
For all of the post-1367 results, bear in mind that the court may, in proper circumstances, choose to decline to exercise its supplemental jurisdiction. See § 1367(c). Similarly, under pre-1367 laws, courts had some discretion to decline jurisdiction over pendent claims and, to a lesser degree, ancillary claims. See United Mine Workers v. Gibbs, 383 U.S. 715 (1966) (pendent jurisdiction); Joiner v. Diamond M. Drilling Co., 677 F.2d 1035 Cir. 1982) (ancillary jurisdiction); Coleman v. Casey Bd. of Educ., 686 F.2d 428 Cir. 1982) (ancillary jurisdiction).
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.

Mathematica »
The #1 tool for creating Demonstrations
and anything technical.
Wolfram|Alpha »
Explore anything with the first
computational knowledge engine.
MathWorld »
The web's most extensive
mathematics resource.
Course Assistant Apps »
An app for every course—
right in the palm of your hand.
Wolfram Blog »
Read our views on math,
science, and technology.
Computable Document Format »
The format that makes Demonstrations
(and any information) easy to share and
interact with.
STEM Initiative »
Programs & resources for
educators, schools & students.
Computerbasedmath.org »
Join the initiative for modernizing
math education.
Step-by-Step Solutions »
Walk through homework problems one step at a time, with hints to help along the way.
Wolfram Problem Generator »
Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet.
Wolfram Language »
Knowledge-based programming for everyone.
Powered by Wolfram Mathematica © 2018 Wolfram Demonstrations Project & Contributors  |  Terms of Use  |  Privacy Policy  |  RSS Give us your feedback
Note: To run this Demonstration you need Mathematica 7+ or the free Mathematica Player 7EX
Download or upgrade to Mathematica Player 7EX
I already have Mathematica Player or Mathematica 7+