Hanna v. Plumer (1964)
- Docket
- 171
- Decided
- 1964-01-01
Summary
Question: How should the court determine whether to apply the state or federal rule? Conclusion: In cases when it is rationally possible to classify a law as either substantive or procedural, the federal courts have the authority to control their own practice and pleading procedures. In a unanimous decision authored by Justice Warren, the Court ruled for Hanna. To raise the Erie doctrine, the Court reasoned, the effect of a procedural rule on the outcome of a case must abridge, enlarge, or modify the substantive law. There was no change to a substantive right here because the plaintiff simply could refile the case or serve the defendant personally. This issue thus related only to procedural requirements, so applying the outcome-determinative test was not appropriate.