Byars v. United States
The Supreme Court threw out counterfeit whiskey-stamp evidence because a federal prohibition agent had joined city police in a search carried out under a search warrant that violated the Fourth Amendment.
Even though a local officer held the warrant, the Court found the federal agent took part as a federal officer and claimed the seized items for the federal government, making the whole search a joint federal-state operation that the Constitution barred.
“A search prosecuted in violation of the Constitution is not made lawful by what it brings to light”
Explaining that illegally obtained evidence isn't excused just because it uncovers a crime.
How it got here: A federal trial court in Iowa convicted the defendant using the stamps as evidence after denying his motion to return them; the court of appeals affirmed.
The Case in Depth
What happened
A man named A. J. Byars was prosecuted in federal court for possessing counterfeit stamps used on bonded whiskey bottles. The stamps were found during a raid on his home that was launched under a state search warrant for illegal liquor, conducted by city police officers who invited a federal prohibition agent along, and who ended up keeping the stamps he and others found.
The question before the Court
Could stamps seized by a federal prohibition agent working alongside city police under a defective state search warrant be used as evidence in federal court?
Why it matters
The ruling stops federal and local police from teaming up to sidestep constitutional search limits: a federal agent cannot piggyback on a legally defective state warrant and then keep whatever evidence turns up for a federal prosecution. It reinforces that courts must look past appearances to see whether a search was really a joint federal effort.
What changes now
The judgment of conviction is reversed, meaning the stamps cannot be used as evidence against the defendant and the case cannot stand as decided. This is a final decision on the legal question of whether the search violated the Constitution, though further proceedings in the lower courts may follow to determine whether the prosecution can proceed without the excluded evidence.
What this does not decide
The Court did not question the general rule that the federal government may use evidence improperly seized by state officers acting entirely on their own, independent of any federal involvement. Its holding is limited to situations where federal agents themselves participate in the wrongful search as federal officers.
Concurrences and dissents
How the Justices voted
Majority (1). Justice Sutherland (author).
How the Court got there
The legal reasoning, step by step
- The Court first found the state search warrant itself invalid under the Fourth Amendment because the underlying affidavit gave only a bare assertion of belief, without stating specific facts supporting probable cause.
- Because evidence obtained through an unconstitutional search cannot be used against the person searched once a timely objection is raised, the key question became whether this was truly a federal search rather than a purely state one.
- The Court examined the facts closely, noting courts must be alert to circumventions of constitutional protections through indirect or informal arrangements between federal and local officers.
- The Court found that the federal prohibition agent was specifically sought out and brought along because of his federal role, not as a private citizen, and that he retained exclusive custody of all the seized stamps as belonging to federal interests rather than any state offense.
- Concluding that the agent participated under color of his federal office, the Court treated the raid as effectively a joint federal-state operation, meaning the search had to meet federal constitutional requirements.
- Since the warrant failed those requirements, the Court held that evidence obtained through the joint search could not be used against the defendant in federal court.