Katz v. United States’s Empirical Analysis
1967
Citation profile
5,627 federal appellate · 1,317 district · 11,979 state decisions
How this case has been cited
Cited by 23,275 later decisions (431 by the Supreme Court) — most recently June 2026 · most notably Terry v. Ohio (1968), Harlow v. Fitzgerald (1982)
5,627 federal appellate · 1,317 district · 11,979 state decisions — followed in 50 states
Later decisions citing this case, by decade. The current decade is in progress, and our corpus holds fewer opinions from the most recent years, so the latest bars are undercounted — not a real decline.
Appellate journey
reviewedKatz v. United States (from Ninth Circuit Court of Appeals)
Relationships
Relies on Wong Sun v. United States · Carroll v. United States · Mapp v. Ohio · Brinegar v. United States
Cited together with Terry v. Ohio · Rakas v. Illinois · Jones v. United States · Coolidge v. New Hampshire · Chimel v. California
Most-quoted passages
The sentences later courts lift from this opinion, ranked by how many decisions quote each — the parts of the opinion doing the work. These counts are smaller than the citation total above because most of the 23,275 citing decisions cite the case generally; a passage count includes only decisions quoting that exact language verbatim.
“The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”
1,150 later decisions quote this exact passage · from the majority““When one man speaks to another he takes all the risks ordinarily inherent in so doing, including the risk that the man to whom he speaks will make public what he has heard. * * * It is but a logical and reasonable extension of this principle that a man take the risk that his hearer, free to memorize what he hears for later verbatim repetition, is instead recording it or transmitting it to another.””
12 later decisions quote this exact passage · from the concurrence“Whether safeguards other than prior authorization by a magistrate would satisfy the Fourth Amendment in a situation involving the national security is a question not presented by this case.”
8 later decisions quote this exact passage · from the concurrence
How this case has been treated — in progress
Whether each later court followed, distinguished, criticized, or overruled this decision. The treatment classification (task #35) runs highest-cited cases first and lights up here as it reaches this one.