Path to the Supreme Court
Potter Stewart — born in Jackson, Michigan, raised in Cincinnati Republican royalty, Yale twice over — was a Sixth Circuit judge at thirty-nine and a recess appointee to the Court at forty-three, confirmed 70–17 in 1959 over southern senators still relitigating Brown. He became the model of the professional judge: no bloc, no program, case by case for twenty-three years.
On the Supreme Court
Stewart's one-liners entered the language — hard-core pornography defied definition, 'but I know it when I see it' — yet the craft ran deeper than the wit. Katz v. United States rebuilt the Fourth Amendment around people, not places. His Griswold dissent called Connecticut's contraception ban 'an uncommonly silly law' that the Constitution nonetheless tolerated — and when Roe arrived he accepted the precedent he had resisted. On capital punishment he supplied both hinges: in Furman, death as then administered was 'cruel and unusual in the same way that being struck by lightning is cruel and unusual'; four years later his joint opinion in Gregg restored it under guided discretion. He retired young, at sixty-six, in 1981 — opening the seat for Sandra Day O'Connor (§102) — and died four years later.
The Voting Record
How Stewart voted in the 3,518 cases the Supreme Court Database records from the 1958 term through the 1980 term, using that database’s classification of each vote as liberal or conservative. The gold tick on each bar is the rate for the other justices sitting on those same cases.
Across the whole career Stewart voted with Powell more than with anyone else — the same side of the judgment in 72.6% of their 959 divided cases — and with Douglas least, at 43.3%. See the matrices →Compared against the 14 colleagues Stewart shared at least 300 divided cases with.
And Stewart ended 6.6 points more liberal relative to those colleagues than at the start — the 14th-largest shift of the 27 justices with a long enough record to measure. See who changed →
Source · The Supreme Court Database (Spaeth, Epstein, Nelson, Martin, et al.) · how these figures are made
Key Decisions
Jacobellis v. Ohio
1964Holding · An Ohio obscenity conviction was reversed; only 'hard-core pornography' may be criminalized.
Role · Stewart concurred: 'I know it when I see it, and the motion picture involved in this case is not that.'
The most famous shrug in the U.S. Reports — candor about definition that doctrine never escaped.
Read the opinion →Katz v. United States
1967Holding · Wiretapping a public phone booth is a Fourth Amendment search requiring a warrant.
Role · Stewart wrote the majority.
'The Fourth Amendment protects people, not places' — the foundation of privacy doctrine in the electronic age.
Read the opinion →Furman v. Georgia
1972Holding · The death penalty as then administered was unconstitutional, 5–4, in a one-paragraph per curiam with nine opinions.
Role · Stewart concurred on the arbitrariness of its infliction.
'Cruel and unusual in the same way that being struck by lightning is cruel and unusual' — the concurrence that framed the modern death-penalty debate.
Read the opinion →Gregg v. Georgia
1976Holding · Guided-discretion capital statutes are constitutional; the death penalty resumed.
Role · Stewart announced the judgment in the joint lead opinion with Powell (§99) and Stevens (§101).
With Furman, Stewart authored both poles of American capital-punishment law.
Read the opinion →Go Deeper
Potter Stewart is the moderate at the center of the Warren and Burger Courts — the Cincinnati Republican, son of an Ohio judge, whom Eisenhower named in 1958, and who spent twenty-three years as a pragmatic, unideological swing vote resistant to the grand theories of both wings. He is remembered above all for four words: writing on hard-core pornography in Jacobellis v. Ohio, he declined to define it but said, 'I know it when I see it' — perhaps the most famous phrase in the U.S. Reports. His most important opinion, Katz v. United States, remade Fourth Amendment law with the principle that 'the Fourth Amendment protects people, not places,' launching the 'reasonable expectation of privacy' test that governs surveillance to this day. He has no full biography; approach him through the Friedman & Israel chapter, the privacy and obscenity opinions, and the reference literature.
The Bookshelf
The fullest short life of a justice who never got a full biography. The Chelsea House chapter draws the moderate clearly: the Yale-educated Cincinnati lawyer and city councilman, the appeals-court judge, and the Supreme Court centrist who distrusted absolutes and decided case by case. It is good on the independence that made him unpredictable — a Republican who joined many Warren Court landmarks and dissented from others — and on the craftsmanship of his opinions. The starting point for a justice defined by his refusal to be defined.
Stewart's most important opinion, and the foundation of modern surveillance law. Overruling the trespass-based approach of Olmstead (which Brandeis §67 had attacked in dissent), he held that the government's warrantless wiretap of a public phone booth violated the Fourth Amendment because 'the Fourth Amendment protects people, not places' — and Justice Harlan's (§89) concurrence distilled the holding into the 'reasonable expectation of privacy' test that still governs everything from wiretaps to cell-site tracking. The vindication of Brandeis, and the charter of digital-age privacy. Free online.
The most quoted line in Supreme Court history, and a candid confession of the limits of legal definition. Concurring in the reversal of an obscenity conviction over a French art film, Stewart wrote that criminally obscene 'hard-core pornography' may be impossible to define intelligibly, 'But I know it when I see it, and the motion picture involved in this case is not that.' Mocked as subjectivity dressed as law and praised as honesty about the limits of rules, the phrase became shorthand for the whole intractable problem of regulating expression. Free online.
The reliable short account — the Ohio judicial family, the Yale years, the moderate Republican appointment, and the twenty-three years as a centrist swing vote — in a few well-sourced pages with a portrait. Good on the death-penalty role (his 'wanton and freakish' formula in Furman and his part in reviving capital punishment in Gregg) that a phrase-based memory tends to crowd out. The best compact, citable life. CQ Press for the SCHS.
Stewart's famous Yale address — the argument that the Press Clause is a structural protection for the institutional press, not a redundancy of free speech. The founding text of modern press-clause scholarship, from the justice who also gave us 'I know it when I see it.' Free full text.
The leading study of the doctrine Stewart owned — the author of Katz and its 'reasonable expectation of privacy,' assessed by a leading judicial historian. The title phrase is the standard characterization of the justice no one has yet given a biography.
The standard modern biographical encyclopedia of the Court: a signed essay on each of the 110 justices from Jay to Alito, alphabetically arranged, by a named scholar or journalist. Length tracks reputation — two pages for Thomas Johnson, three for Woods, eleven for Holmes — which is itself a rough map of who the literature has bothered with. It is not a substitute for a biography, and for the justices who have never had one it is often the most careful short account in print. Borrow it free at the Internet Archive.
The one-volume reference on the Court: more than a thousand signed entries on cases, doctrines, institutions and the justices, current to 2005. Cases and people share one alphabet, so a citation can be followed without changing volumes, and the biographical entries are short, written by specialists, and better than a longer sketch at carrying the historiography — what the argument about a justice currently is. Borrow it free at the Internet Archive.
The Reading Path
A researched route through the literature — in order.
- 1.The Friedman & Israel chapter — for the moderate who refused the grand theories
- 2.Katz v. United States — for 'people, not places' and the birth of privacy doctrine
- 3.Jacobellis v. Ohio — for 'I know it when I see it' and the limits of definition
- 4.The SCHS Illustrated Biographies — for the capsule life and the death-penalty role
Where the Papers Are Kept
The Potter Stewart papers are held at Yale, his alma mater — a substantial collection of case files, correspondence, and conference notes that, for a justice without a biography, is the principal record of his twenty-three years and a valuable source on the internal life of the Warren and Burger Courts. Visit →
Online Resources
Ideas for Further Research
- The phrase and the man. Stewart is remembered for four words about pornography and forgotten for Katz, one of the most important opinions of the century. Ask what it means that a serious justice's legacy collapses into a quip, and use the gap between 'I know it when I see it' and 'the Fourth Amendment protects people, not places' to study how the Court's history is flattened by its most quotable lines.
- The reasonable expectation of privacy. Katz built Fourth Amendment law on what society is prepared to recognize as a reasonable expectation of privacy — a test that has strained under wiretaps, thermal imaging, GPS, cell-site data, and the cloud. Trace the doctrine from 1967 to Carpenter (2018) and beyond, and ask whether Stewart's people-not-places insight can survive a world of ubiquitous digital surveillance.
- The virtue of no theory. Stewart prided himself on deciding cases rather than building systems, distrusting the absolutism of Black (§76) and Douglas (§79) alike. Assess the case for the unideological swing justice — the pragmatic center that decides which way the Court tips — and ask whether such a figure is a stabilizing virtue or an evasion of the judge's duty to say what the law is. Seat lineage: Burton §84 → Stewart → Sandra Day O'Connor §102.