Wisconsin Public Intervenor v. Ralph Mortier
501 U.S. 597 · Decided June 21, 1991 · Supreme Court of the United States
Record summary. This page is generated from the Supreme Court Database’s coded data about the case. It describes who decided what, not the Court’s reasoning. Read the opinion itself before relying on it. Not legal advice.
At a glance
Wisconsin Public Intervenor v. Ralph Mortier was decided on June 21, 1991 unanimously (9–0). The Court reversed the lower court's decision and remanded the case. Justice Byron R. White wrote the opinion of the Court. SCDB classifies its main issue as “Federal preemption of state legislation or regulation” in the Federalism area.
Read the opinion
Case details
- Citations
- 501 U.S. 597 · 111 S. Ct. 2476 · 115 L. Ed. 2d 532 · 1991 U.S. LEXIS 3632
- Docket number
- 89-1905
- Decided
- June 21, 1991
- Argued
- April 24, 1991
- Court era
- Rehnquist Court
- Decision type
- Opinion of the Court (orally argued)
- Disposition
- Reversed and remanded
- Outcome for petitioner
- The petitioning party received a favorable disposition
- Vote
- 9–0 (unanimous)
- Majority opinion
- Byron R. White
- Opinion assigned by
- William H. Rehnquist
- How the case arrived
- Certiorari
- Issue area
- Federalism
- Legal provision
- Federal Insecticide, Fungicide, and Rodenticide Act
- Type of law
- Federal statute
- Decision direction (SCDB)
- Conservative what this means
How the Justices voted
| Justice | Vote | Separate writing |
|---|---|---|
| Justice Byron R. White | Majority | Wrote an opinion |
| Justice Thurgood Marshall | Majority | |
| Justice Harry A. Blackmun | Majority | |
| Chief Justice William H. Rehnquist | Majority | |
| Justice John Paul Stevens | Majority | |
| Justice Sandra Day O'Connor | Majority | |
| Justice Antonin Scalia | Special concurrence | Wrote an opinion |
| Justice Anthony M. Kennedy | Majority | |
| Justice David H. Souter | Majority |
Full case caption
Wisconsin Public Intervenor, et al. v. Ralph Mortier, et al.
SCDB identifiers: case 1990-118, docket 1990-118-01.
Related decisions
Other cases on “Federal preemption of state legislation or regulation”
- Ingersoll-Rand Company v. Perry McClendon
- FMC Corporation v. Cynthia Ann Holliday
- Dan Morales v. Trans World Airlines, Inc.
- Vera M. English v. General Electric Company
- California v. Federal Energy Regulatory Commission
- Adams Fruit Co., Inc. v. Barrett
Cases on the same legal provision: Federal Insecticide, Fungicide, and Rodenticide Act
Same Term, same area (Federalism)
- United States of America v. State of Louisiana
- State of Mississippi v. United States
- FMC Corporation v. Cynthia Ann Holliday
- Ingersoll-Rand Company v. Perry McClendon
- James B. Beam Distilling Co. v. Georgia
Source: Supreme Court Database, 2026 Release 01 (data file dated September 8, 2026). Imported into CaseTrail November 5, 2026. Coverage: decisions from the 1946 through 2025 Terms. Methodology · Report an error