The defendants appealed the Second Circuit's decision to the Supreme Court in Dennis v. United States.
During the Supreme Court appeal, the defendants were assisted by the National Lawyers Guild and the ACLU.
The Supreme Court limited its consideration to the questions of the constitutionality of the Smith Act and the jury instructions, and did not rule on the issues of impartiality, jury composition, or informant witnesses.
The 6–2 decision was issued on June 4, 1951, and upheld Hand's decision.
Chief Justice Fred Vinson's opinion stated that the First Amendment does not require that the government must wait "until the putsch is about to be executed, the plans have been laid and the signal is awaited" before it interrupts seditious plots.
In his opinion, Vinson endorsed the balancing approach used by Judge Hand:
Chief Judge Learned Hand ... interpreted the [clear and present danger] phrase as follows: 'In each case, [courts] must ask whether the gravity of the "evil", discounted by its improbability, justifies such invasion of free speech as is necessary to avoid the danger.'
We adopt this statement of the rule.
As articulated by Chief Judge Hand, it is as succinct and inclusive as any other we might devise at this time.
It takes into consideration those factors which we deem relevant, and relates their significances.
More we cannot expect from words.

Vinson's opinion also addressed the contention that Medina's jury instructions were faulty.
The defendants claimed that Medina's statement that "as matter of law that there is sufficient danger of a substantive evil that the Congress has a right to prevent to justify the application of the statute under the First Amendment of the Constitution" was erroneous, but Vinson concluded that the instructions were an appropriate interpretation of the Smith Act.

The Supreme Court was, in one historian's words, "bitterly divided" on the First Amendment issues presented by Dennis.
Justices Hugo Black and William O. Douglas dissented from the majority opinion.
In his dissent, Black wrote "public opinion being what it now is, few will protest the conviction of these Communist petitioners.
There is hope, however, that, in calmer times, when present pressures, passions and fears subside, this or some later Court will restore the First Amendment liberties to the high preferred place where they belong in a free society."
Following the Dennis decision, the Court utilized balancing tests for free speech cases, and rarely invoked the clear and present danger test.
The defendants appealed the Second Circuit's decision to the Supreme Court in Dennis v. United States. During the Supreme Court appeal, the defendants were assisted by the National Lawyers Guild and the ACLU. The Supreme Court limited its consideration to the questions of the constitutionality of the Smith Act and the jury instructions, and did not rule on the issues of impartiality, jury composition, or informant witnesses. The 6–2 decision was issued on June 4, 1951, and upheld Hand's decision. Chief Justice Fred Vinson's opinion stated that the First Amendment does not require that the government must wait "until the putsch is about to be executed, the plans have been laid and the signal is awaited" before it interrupts seditious plots. In his opinion, Vinson endorsed the balancing approach used by Judge Hand:
Chief Judge Learned Hand ... interpreted the [clear and present danger] phrase as follows: 'In each case, [courts] must ask whether the gravity of the "evil", discounted by its improbability, justifies such invasion of free speech as is necessary to avoid the danger.' We adopt this statement of the rule. As articulated by Chief Judge Hand, it is as succinct and inclusive as any other we might devise at this time. It takes into consideration those factors which we deem relevant, and relates their significances. More we cannot expect from words.
Vinson's opinion also addressed the contention that Medina's jury instructions were faulty. The defendants claimed that Medina's statement that "as matter of law that there is sufficient danger of a substantive evil that the Congress has a right to prevent to justify the application of the statute under the First Amendment of the Constitution" was erroneous, but Vinson concluded that the instructions were an appropriate interpretation of the Smith Act.
The Supreme Court was, in one historian's words, "bitterly divided" on the First Amendment issues presented by Dennis. Justices Hugo Black and William O. Douglas dissented from the majority opinion. In his dissent, Black wrote "public opinion being what it now is, few will protest the conviction of these Communist petitioners. There is hope, however, that, in calmer times, when present pressures, passions and fears subside, this or some later Court will restore the First Amendment liberties to the high preferred place where they belong in a free society." Following the Dennis decision, the Court utilized balancing tests for free speech cases, and rarely invoked the clear and present danger test.
Smith Act trials of Communist Party leaders