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Supreme Court · Decisions

Dennis et al. v. United States

The Court ruled that Dennis did not have the right under the First Amendment to the United States Constitution to exercise free speech, publication and assembly, if the exercise involved the creation of a plot to overthrow the government.

341 U.S. 494 · No. 336 · 1950 term · Vinson Court

Decided Jun 4, 1951 · argued Dec 4, 1950

First Amendment · Federal or state internal security legislation: Smith, Internal Security, and related federal statutes

Majority opinion: Frederick Vinson

The voteMajorityDissent

6–26 in the majority, 2 in dissent

2 dissents (7–2)

Affirmed. Dennis et al. lost.

What this ruling means

Affirmed: the Supreme Court upheld the decision of the U.S. Court of Appeals, Second Circuit, so it stands (sometimes with changes the Court made to it).

Dennis et al. was the petitioner, the side that asked the Supreme Court to review the case. “Lost” means the Court did not give that side the result it asked for.

From the Supreme Court Database. A justice who agreed with the result but not the reasoning counts in the majority.

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Summary

The opening of the case’s Wikipedia article: what the case was about and what the Court held.

Dennis v. United States, 341 U.S. 494 (1951), was a United States Supreme Court case relating to Eugene Dennis, General Secretary of the Communist Party USA. The Court ruled that Dennis did not have the right under the First Amendment to the United States Constitution to exercise free speech, publication and assembly, if the exercise involved the creation of a plot to overthrow the government. In 1969, Dennis was de facto overruled by Brandenburg v. Ohio.

Read the full article on Wikipedia

Data notes

The text is Wikipedia’s (CC BY-SA 4.0), matched to the case by its citation, docket number or name and year, and is not checked against the opinion. The site keeps the article’s opening section, ending on its last full sentence. The one-sentence summary under the title is the Decisions list’s: Wikipedia’s own ruling sentence, or, tagged “AI-written”, one Claude wrote from this opening.

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How the justices voted

Each justice who took part, placed by their Martin–Quinn ideology score for the 1950 term. Filled: the 6 in the majority. Hollow: the 2 in dissent. Colour is the party of the president who appointed them.

More liberalMore conservativeMedianBlackDouglasFrankfurterR. JacksonBurtonReedVinsonMinton

Majority(6)

Dissent(2)

Did not take part: Tom Clark.

Data notes

Each justice’s vote and what they wrote are from the justice-centered file of the Supreme Court Database. “Wrote a concurrence” means the justice sided with the majority and wrote separately; a justice who dissented in part is counted on the side they took overall. A justice who wrote nothing is listed as joining their side.

Positions are each justice’s Martin–Quinn score for the case’s term, the same scores as the Ideology page: negative is more liberal, positive more conservative. A score sums up a justice’s votes across the whole term, so it says where they usually sit, not why they voted as they did here. The median line is the Court’s median justice that term.

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The parties

Who brought the case to the Court, who answered it, and how it got there.

Petitioner
Dennis et al.Person accused, indicted, or suspected of crime
Respondent
United StatesUnited States
Reached the Court by
Certiorari (the Court chose to hear it)
Data notes

The names are the two sides of the case’s title. The description under each is the Supreme Court Database’s category for that party, in its own wording. The petitioner is the side that asked the Supreme Court to review the decision below. “Why it was taken” appears only when the majority opinion says lower courts disagreed or were unsure about the question; reasons that would fit any case (“to resolve the question presented”, “an important question”) are left out.

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The law at issue

The law the Court was asked to apply, and the kind of power it used to decide.

Provision
Fifth Amendment (due process)
Kind of law
Constitutional Amendment
Decided by
Judicial review (national level)
Data notes

The Supreme Court Database codes the main constitutional provision, statute or court rule each case turned on, and the basis of the decision: judicial review of a federal or state law, interpreting a statute, supervising the lower courts, and so on. A case can rest on more than one. “Overruled” counts only where the majority opinion says so.

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Timeline

What happened at the Court and how the case got there, newest first.

  1. Jun 4, 1951DecidedDecided · Decided 6–2: affirmed. Dennis et al. lost.
  2. Dec 4, 1950ArguedArgued · Oral argument before the Court.
  3. Not datedTaken upTaken up · The Supreme Court agreed to hear the case (certiorari).
  4. Not datedCourt belowCourt below · Decided by the U.S. Court of Appeals, Second Circuit: affirmed.
  5. Not datedBeganBegan · The case began in the New York Southern U.S. District Court.
Data notes

From the Supreme Court Database: the court the case began in, the court whose decision the Supreme Court reviewed and what that court did, how the case came to the Court, and the dates of argument and decision. The database does not date the steps in the lower courts. Court names are the database’s.

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Other decisions on the same issue

33 other argued cases since 1946 on federal or state internal security legislation: Smith, Internal Security, and related federal statutes, newest first.

  1. Tiktok, Inc. v. Garland145 S. Ct. 57Jan 17, 2025 · 145 S. Ct. 57First Amendment9–0Unanimous band

  2. Eric H. Holder, Jr., Attorney General, et al. v. Humanitarian Law Project et al.561 U.S. 1Jun 21, 2010 · 561 U.S. 1First Amendment6–36–3 band

  3. Regan, Secretary of the Treasury, et al. v. Wald et al.468 U.S. 222Jun 28, 1984 · 468 U.S. 222First Amendment5–45–4 band

  4. Haig, Secretary of State v. Agee453 U.S. 280Jun 29, 1981 · 453 U.S. 280First Amendment7–27–2 band

  5. Kleindienst, Attorney General, et al. v. Mandel et al.408 U.S. 753Jun 29, 1972 · 408 U.S. 753First Amendment6–36–3 band

  6. Bryson v. United States396 U.S. 64Dec 8, 1969 · 396 U.S. 64First Amendment6–27–2 band
  7. Schneider v. Smith, Commandant, United States Coast Guard390 U.S. 17Jan 16, 1968 · 390 U.S. 17First Amendment8–0Unanimous band
  8. United States v. Robel389 U.S. 258Dec 11, 1967 · 389 U.S. 258First Amendment6–27–2 band

  9. Travis v. United States385 U.S. 491Jan 10, 1967 · 385 U.S. 491First Amendment9–0Unanimous band
  10. United States v. Laub et al.385 U.S. 475Jan 10, 1967 · 385 U.S. 475First Amendment9–0Unanimous band
  11. Dennis et al. v. United States384 U.S. 855Jun 20, 1966 · 384 U.S. 855First Amendment7–27–2 band

  12. Albertson et al. v. Subversive Activities Control Board382 U.S. 70Nov 15, 1965 · 382 U.S. 70First Amendment8–0Unanimous band

  13. United States v. Brown381 U.S. 437Jun 7, 1965 · 381 U.S. 437First Amendment5–45–4 band

  14. Zemel v. Rusk, Secretary of State, et al.381 U.S. 1May 3, 1965 · 381 U.S. 1First Amendment6–36–3 band

  15. Veterans of the Abraham Lincoln Brigade v. Subversive Activities Control Board380 U.S. 513Apr 26, 1965 · 380 U.S. 513First Amendment5–36–3 band
  16. American Committee for Protection of Foreign Born v. Subversive Activities Control Board380 U.S. 503Apr 26, 1965 · 380 U.S. 503First Amendment5–36–3 band
  17. Aptheker et al. v. Secretary of StateLandmark · Freedom of movement378 U.S. 500Jun 22, 1964 · 378 U.S. 500First Amendment6–36–3 band
  18. Rabinowitz et al. v. Kennedy, Attorney General376 U.S. 605Mar 30, 1964 · 376 U.S. 605First Amendment9–0Unanimous band
  19. Killian v. United States368 U.S. 231Dec 11, 1961 · 368 U.S. 231First Amendment5–45–4 band
  20. Communist Party, U. S. A., et al. v. Catherwood, Industrial Commissioner367 U.S. 389Jun 12, 1961 · 367 U.S. 389First Amendment9–0Unanimous band
  21. Noto v. United States367 U.S. 290Jun 5, 1961 · 367 U.S. 290First Amendment9–0Unanimous band

  22. Scales v. United States367 U.S. 203Jun 5, 1961 · 367 U.S. 203First Amendment5–45–4 band

  23. Communist Party of the United States v. Subversive Activities Control Board367 U.S. 1Jun 5, 1961 · 367 U.S. 1First Amendment5–45–4 band

  24. Travis v. United States364 U.S. 631Jan 16, 1961 · 364 U.S. 631First Amendment6–36–3 band
  25. Dayton v. Dulles, Secretary of State357 U.S. 144Jun 16, 1958 · 357 U.S. 144First Amendment5–45–4 band
  26. Kent et al. v. Dulles, Secretary of StateLandmark · Freedom of movement357 U.S. 116Jun 16, 1958 · 357 U.S. 116First Amendment5–45–4 band

  27. Rowoldt v. Perfetto, Acting Officer in Charge, Immigration and Naturalization Service355 U.S. 115Dec 9, 1957 · 355 U.S. 115First Amendment5–45–4 band
  28. Cole v. Young et al.351 U.S. 536Jun 11, 1956 · 351 U.S. 536First Amendment6–36–3 band
  29. Communist Party of the United States v. Subversive Activities Control Board351 U.S. 115Apr 30, 1956 · 351 U.S. 115First Amendment6–36–3 band

  30. Pennsylvania v. Nelson350 U.S. 497Apr 2, 1956 · 350 U.S. 497First Amendment6–36–3 band

  31. Harisiades v. Shaughnessy, District Director of Immigration and Naturalization342 U.S. 580Mar 10, 1952 · 342 U.S. 580First Amendment6–27–2 band

  32. Carlson et al. v. Landon, District Director of Immigration and Naturalization Service342 U.S. 524Mar 10, 1952 · 342 U.S. 524First Amendment5–45–4 band
  33. American Communications Assn., C. I. O., et al. v. Douds, Regional Director of the National Labor Relations Board339 U.S. 382May 8, 1950 · 339 U.S. 382First Amendment5–18–1 band

Data notes

Every other orally argued case with a clear vote, from the 1946 term on, that the Supreme Court Database files under the same issue as this one. The database gives each case one issue from a list of about 270 (abortion, search and seizure of vehicles, the death penalty, and so on), whatever law it turned on.

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Official record

Read the full opinion on Justia and Wikipedia. Case data from the Supreme Court Database, Version 2026 Release 01, through the 2025 term.