Federal Question Jurisdiction

In the most recent post, I outlined the important points concerning diversity jurisdiction. Diversity jurisdiction is one avenue for getting a case into federal court. The other is federal question jurisdiction.

The district federal courts have original jurisdiction over all civil actions arising under the Constitution, laws, or treaties of the United States. It's important to note that the federal question for which jurisdiction is based must appear as part of plaintiff's cause of action. In other words, the fact that there is an asserted defense that implicates a federal question is not sufficient to confer jurisdiction if plaintiff has not also asserted a federal question.

It gets a bit more complex when there are multiple claims, some of which assert a federal question, and some of which do not. In such instances the federal court will have discretion (as per its pendent jurisdiction) to hear all claims that derive from a "common nucleus of operative fact." That's a rather odd way of stating the idea, but what it means is that if the claims all arise from the same set of facts, then the the fact that some of the claims are based on state law will not prevent a federal court from hearing those state-law claims provided there is at least one federal claim to warrant jurisdiction. And even if the federal claim on which jurisdiction is based ends up getting dismissed after trial has commenced, the federal court may still exercise pendent jurisdiction over the state claims.

It's also possible that questions may arise in which plaintiff sues more than one defendant, and there is a federal claim against only one of the defendants. Here, too, pendent jurisdiction (specifically, pendent-party jurisdiction) will allow the federal court to hear the non-federal claims against all defendants provided that the claims once again derive from a "common nucleus of operative fact."

***note that the term pendent jurisdiction is interchangeable with the term supplemental jurisdiction.