Montana v. United States
The Supreme Court ruled that the United States could not relitigate the constitutionality of Montana's tax on public construction contractors, because the government had secretly controlled and financed an earlier state lawsuit raising the identical claim and lost.
The decision extends collateral estoppel (the rule against re-arguing an issue already decided) to a nonparty like the federal government when it directs and pays for someone else's lawsuit, and it means the government cannot sidestep an unfavorable state ruling by filing its own case in federal court.
“Thus, although not a party, the United States plainly had a sufficient "laboring oar" in the conduct of the state-court litigation to actuate principles of estoppel.”
Explains why the government's control over the earlier lawsuit bound it to that result.
How it got here: After a contractor's state-court challenge to the tax (financed by the U.S.) failed, a federal district court reached the merits of the government's own separate suit and struck down the tax; Montana appealed directly to the Supreme Court.
The Case in Depth
What happened
A construction company building a federal dam in Montana challenged the state's one-percent tax on public (but not private) construction contractors, arguing it unfairly burdened the federal government and its contractors. The United States secretly directed and paid for that lawsuit. After the Montana Supreme Court upheld the tax, the federal government separately sued in federal court making the same constitutional argument in its own name.
The question before the Court
After the U.S. government secretly ran a contractor's lawsuit against Montana's construction tax and lost, could the government sue again in its own name over the same tax?
Why it matters
Governments and other repeat litigants who fund and control someone else's lawsuit behind the scenes cannot get a second bite at the apple by suing again under their own name if the first case comes out badly. This curbs strategic relitigation and forces parties who exercise real control over litigation to live with the result, even without being formally named.
What changes now
Because the Court resolved the case entirely on collateral estoppel grounds, it did not reach the underlying Supremacy Clause question of whether Montana's tax actually discriminates against the federal government. The district court's judgment striking down the tax is reversed, meaning the tax stands as applied to this dispute. The broader constitutional question about discriminatory state taxation of federal contractors remains open for future cases not barred by an earlier judgment.
What this does not decide
The Court did not decide whether Montana's gross receipts tax actually violates the Supremacy Clause by discriminating against the federal government or its contractors. It resolved the case purely on procedural grounds — that the government was barred from relitigating that question — leaving the underlying constitutional merits undecided.
Concurrences and dissents
Concurrence — Justice Rehnquist
Justice Rehnquist joined the majority opinion but wrote separately to clarify that he did not want the Court's citations to law review articles and draft or final versions of the Restatement of Judgments to be read as endorsing those sources' views on issues not actually presented by this case's facts.
Dissent — Justice White
“It is not a law generally embracing all similarly situated state constituents doing business in the private and public sectors.”White's core objection that Montana's tax unfairly singled out public-sector contractors.
Justice White argued the government was not estopped from suing, because the Montana Supreme Court's earlier ruling had rested on the assumption that the tax would be largely offset by credits, an assumption that no longer held true by the time of the federal suit, changing the facts enough to defeat preclusion. On the merits, he argued the tax was unconstitutional because it discriminated against federal contractors by taxing only public-sector contractors while exempting private-sector ones, undermining the political check against abusive taxation that the Constitution requires.
How the Court got there
The legal reasoning, step by step
- The Court explained that collateral estoppel bars relitigating an issue already actually decided by a competent court, and that this bar can extend to a nonparty who exercised control over the earlier suit even though only a private company was formally named as plaintiff.
- The government had stipulated that it required the first lawsuit to be filed, reviewed and approved the complaint, paid the attorneys, directed the appeal, and even ordered the contractor to abandon a later appeal — showing it had what the Court called a 'laboring oar' in the earlier case, enough to bind it to that result.
- The Court then checked whether the issue in this case was truly the same one already decided: comparing the two complaints, it found the government's federal claims tracked the contractor's earlier state claims almost word for word, so the same constitutional question had already been resolved.
- The Court considered whether the facts or the law had meaningfully changed since the first ruling — noting that although the contractor could not use certain tax credits in the earlier case while later contractors could, the state court's reasoning had never actually depended on that detail, so the change did not undermine the earlier judgment.
- The Court also considered whether any recognized exception to preclusion applied, such as the rule that a pure legal ruling in one unrelated case does not bind parties in a later, different dispute, but found this case involved the same claim, same time period, and same subject matter, so no exception applied.
- Having found the same issue, unchanged facts and law, and no applicable exception, the Court concluded the government was bound by the earlier state court's rejection of its constitutional challenge to the tax.
Doctrinal impact
Cases affected by this decision
Distinguishes Commissioner v. Sunnen (333 U.S. 591)
The Court said this case did not involve the kind of changed facts or law that made collateral estoppel improper in Sunnen.
Reaffirms United States v. Moser (266 U.S. 236)
The Court relied on Moser's rule that only issues, not abstract legal rulings, are conclusively barred from relitigation.
Distinguishes England v. Medical Examiners (375 U.S. 411)
The Court said this case did not involve the unfair forced-choice problem England addressed.