Federal court jurisdiction is limited by design: a federal judge can hear your case only if the Constitution or a federal statute specifically authorizes it. The two most common doorways are a claim arising under federal law and a dispute between citizens of different states where more than $75,000 is at stake. Several narrower bases exist as well. If none of them applies, the judge must dismiss, no matter how strong the merits.1Congress.gov. Constitution of the United States – Article III State courts work the opposite way, handling nearly any kind of dispute, which is why the threshold question in any federal filing is whether the court is even allowed to look at it.
Claims Arising Under Federal Law
The most direct route into federal court is a claim built on the Constitution, a federal statute, or a U.S. treaty. District courts have original jurisdiction over all such cases under 28 U.S.C. § 1331.2Office of the Law Revision Counsel. 28 USC 1331 – Federal Question Typical examples are constitutional claims against a government agency, disputes over the meaning of a federal regulation, and lawsuits enforcing federal consumer-protection or employment statutes.
The federal issue has to show up in the plaintiff’s own complaint, not in an anticipated defense. This is the well-pleaded complaint rule, laid down in Louisville & Nashville Railroad Co. v. Mottley: a suit “arises under” federal law only when the plaintiff’s cause of action is based on that law.3Justia. Louisville and Nashville R. Co. v. Mottley, 211 U.S. 149 (1908) So a state-court breach-of-contract suit does not become a federal case just because the defendant plans to argue that the contract violates federal antitrust law. The federal hook has to be built into the claim itself.
Diversity of Citizenship
When the parties are citizens of different states and more than $75,000 is on the line, a federal court can hear the case even if no federal law is involved. Diversity jurisdiction, codified at 28 U.S.C. § 1332, was created to give out-of-state parties a neutral forum away from potential hometown bias.4Office of the Law Revision Counsel. 28 USC 1332 – Diversity of Citizenship; Amount in Controversy; Costs
Two conditions apply. The amount in controversy must exceed $75,000, not counting interest and costs; exactly $75,000 is not enough. And diversity must be complete, meaning no plaintiff shares state citizenship with any defendant. One overlap on either side destroys federal jurisdiction over the whole case.4Office of the Law Revision Counsel. 28 USC 1332 – Diversity of Citizenship; Amount in Controversy; Costs
For individuals, citizenship means domicile, the state where you live and intend to stay indefinitely. You can only have one domicile at a time. Corporations get a different rule: they are citizens of every state where they are incorporated and of the state where they have their principal place of business.4Office of the Law Revision Counsel. 28 USC 1332 – Diversity of Citizenship; Amount in Controversy; Costs That dual citizenship often keeps large companies out of diversity jurisdiction in states where they have major operations, because they already count as citizens of the plaintiff’s state.
Multiple claims against the same defendant can be added together to clear the $75,000 bar. When multiple plaintiffs are involved, each one generally has to meet the threshold on their own; separate people’s claims cannot be pooled. Joint claims, where two or more parties share a single undivided interest in the dispute, are the exception.
Class Actions Under CAFA
Large class actions follow a looser set of rules under the Class Action Fairness Act. CAFA requires only minimal diversity, meaning at least one class member is a citizen of a different state than any defendant. The dollar threshold shifts too: the aggregate amount in controversy for the entire class must exceed $5 million, and individual class members’ claims can be added together to reach that number.4Office of the Law Revision Counsel. 28 USC 1332 – Diversity of Citizenship; Amount in Controversy; Costs The relaxed standard makes it much easier for defendants in nationwide class actions to pull the case into federal court.
When the United States Is a Party
Cases with the federal government on either side belong in federal court. That covers enforcement actions by agencies like the Department of Justice and suits by private citizens against the government. But there is a catch: the government cannot be sued without its consent. Sovereign immunity means Congress has to pass a statute specifically authorizing the type of claim before you can proceed.
The Federal Tort Claims Act is the most common waiver. It lets individuals seek money damages for personal injury or property damage caused by a federal employee acting within the scope of their job.5United States Courts. Federal Tort Claims Against Federal Judiciary Personnel Other statutes open the door for government contract disputes and certain constitutional violations. If no statute opens the door for your particular claim, the case gets dismissed regardless of how clearly the government is at fault.
Subjects Only Federal Courts Can Hear
Most civil cases that qualify for federal jurisdiction can also be filed in state court. A few subjects, though, are reserved exclusively for federal judges. Filing them in state court is not an option.
- Bankruptcy. Federal district courts have exclusive jurisdiction over all bankruptcy cases, which keeps the process for discharging debts and distributing assets uniform nationwide.6Office of the Law Revision Counsel. 28 USC 1334 – Bankruptcy Cases and Proceedings
- Patents and copyrights. Claims under federal patent or copyright law must go to federal court; state courts are explicitly barred. Trademark disputes are different and can go to either state or federal court.7Office of the Law Revision Counsel. 28 USC 1338 – Patents, Plant Variety Protection, Copyrights, Mask Works, Designs, Trademarks, and Unfair Competition
- Admiralty and maritime. Federal courts have original jurisdiction over civil maritime disputes, including shipping accidents and contracts for work on navigable waters. A “saving to suitors” clause preserves certain common-law remedies in state court, so state courts are not entirely shut out.8Office of the Law Revision Counsel. 28 USC 1333 – Admiralty, Maritime and Prize Cases
Standing to Sue
Even when subject-matter jurisdiction is clear, you still need standing. Article III limits federal judicial power to actual “cases and controversies,” which rules out abstract legal questions and hypothetical disputes.
Three elements have to be shown:9Congress.gov. Overview of Standing – Constitution Annotated
- Injury in fact. A real, concrete harm, not a speculative or hypothetical one.
- Causation. The harm is fairly traceable to the defendant’s conduct, not to some unrelated third party.
- Redressability. A favorable ruling would actually fix or compensate the injury.
Two related doctrines fill out the picture. Ripeness asks whether the dispute has developed enough to warrant a decision. If the harm has not happened yet and might never happen, the court declines to hear it. Mootness is the opposite problem: if the dispute has already been resolved, there is nothing left to decide. Both doctrines keep federal courts focused on live disputes where a ruling will have real consequences.
Related State-Law Claims
Once a federal court has jurisdiction over at least one claim, it can hear related state-law claims that grow out of the same facts. Under 28 U.S.C. § 1367, this supplemental jurisdiction reaches any claim forming part of the same case or controversy as the original federal claim.10Office of the Law Revision Counsel. 28 USC 1367 – Supplemental Jurisdiction If a police officer uses excessive force, a federal civil-rights claim and a state-law assault claim from the same encounter can both go forward in the same federal case.
The power is discretionary. A judge may decline to hear the state-law claims when they raise novel or complex issues of state law, when they substantially dominate the case compared to the federal claim, when all federal claims have been dismissed, or when other exceptional circumstances justify declining.10Office of the Law Revision Counsel. 28 USC 1367 – Supplemental Jurisdiction The third scenario is the most common one in practice: when the federal claim drops out early, the remaining state claims usually go back to state court.
Moving a Case From State to Federal Court
If you are sued in state court but the case could have been filed in federal court, you generally have the right to move it there. Removal lets a defendant transfer the case to the federal district court covering the location of the state lawsuit.11Office of the Law Revision Counsel. 28 USC 1441 – Removal of Civil Actions Only defendants can remove. Plaintiffs made their forum choice when they filed.
Deadlines are strict. The notice of removal has to be filed within 30 days of service of the complaint. If the case was not initially removable but becomes so later because of an amended complaint or other development, a new 30-day window starts when the basis for removal first becomes clear. For diversity cases, removal is barred entirely once more than a year has passed since the lawsuit began, unless the court finds the plaintiff deliberately manipulated the case to block removal.12Office of the Law Revision Counsel. 28 USC 1446 – Procedure for Removal of Civil Actions
Diversity-based removal has one more limit worth knowing. Under the forum-defendant rule, if any properly served defendant is a citizen of the state where the lawsuit was filed, the case cannot be removed on diversity grounds.11Office of the Law Revision Counsel. 28 USC 1441 – Removal of Civil Actions Diversity jurisdiction exists to protect out-of-state parties from local bias, and that concern disappears when the defendant is local. Federal-question cases can be removed no matter where the defendant lives.
Venue: Which Federal Courthouse
Jurisdiction tells you whether a federal court can hear your type of case. Venue tells you which specific federal courthouse is the right one. Jurisdiction without proper venue still gets the case dismissed or transferred, so both have to be satisfied.
Under 28 U.S.C. § 1391, a case can generally be filed in a district where any defendant lives (as long as all defendants are in the same state), or where a substantial part of the events giving rise to the claim occurred.13Office of the Law Revision Counsel. 28 USC 1391 – Venue Generally For individuals, residence means domicile. For corporate defendants, residence means any district where the company is subject to personal jurisdiction. If no district fits either test, you can fall back on any district where a defendant could be hauled into court.
Even where venue is proper, a defendant can ask to move the case somewhere more convenient. Under 28 U.S.C. § 1404, a judge can transfer the case to any district where it could originally have been filed, or where all parties agree to litigate, if the transfer serves the convenience of the parties and witnesses and the interest of justice.14Office of the Law Revision Counsel. 28 U.S. Code 1404 – Change of Venue Courts look at where the evidence sits, how far witnesses would travel, and which forum has the stronger connection to the dispute. This is not a second shot at jurisdiction. It is about finding the most practical courtroom.