28 U.S.C. 1331 gives federal district courts original jurisdiction over civil actions arising under the U.S. Constitution, federal laws, or treaties. It answers whether a federal court has subject-matter authority over the dispute. It does not itself create a claim for damages or prove that a plaintiff should win. [1]
Start with the claim, not a federal reference
The most common route is a cause of action created by federal law. For example, a properly pleaded claim under an applicable federal civil-rights or employment statute may arise under federal law. The plaintiff must still establish the statute’s substantive requirements and satisfy any prerequisites to suit. [2]
Simply mentioning a constitutional amendment or describing unfair conduct does not supply a valid federal claim. A complaint should identify the legal right, the defendant’s relevant conduct, the available remedy, and why that defendant can be sued under the chosen law.
Some state-law claims contain federal issues
In Gunn v. Minton, the Supreme Court described a limited category of state-law claims that can support federal-question jurisdiction. The federal issue must be necessarily raised, actually disputed, substantial to the federal system, and suitable for federal resolution without upsetting Congress’s approved allocation of federal and state judicial responsibility. [2]
Gunn involved legal malpractice arising from patent litigation. The presence of a patent issue did not automatically place that malpractice claim in federal court. An issue can matter greatly to the parties while lacking the broader significance required by that jurisdictional test. [2]
Other filing requirements remain
Section 1331 contains no general minimum dollar amount. However, subject-matter jurisdiction is only one part of filing a case. Personal jurisdiction, venue, standing, service, limitations periods, and the sufficiency of the claims can still defeat or delay the action. [1]
- Identify the actual federal cause of action or embedded federal issue.
- Check whether the statute authorizes the requested remedy.
- Determine whether administrative steps must come first.
- Explain the jurisdictional basis clearly in the complaint.
See administrative prerequisites for an employment discrimination lawsuit and serving court papers and obtaining waivers. A familiar federal citation should be the beginning of the jurisdictional analysis, not its conclusion.
Primary sources
Sources checked: October 31, 2026.