In 1919, the Supreme Court of the United States was asked to review several convictions under the Espionage Act of 1917 and the Sedition Act of 1918, laws that sought to crack down on radical criticism of American participation in World War I. These cases presented the Justices with the first major opportunity in modern times to determine the scope of the First Amendment freedoms of speech and the press.

The Court's response did not augur well for civil liberties. In early March, it unanimously upheld the convictions of two Socialist Party officials for urging citizens to oppose the draft. Justice Oliver Wendell Holmes declared that speech could be restricted whenever it presented “a clear and present danger” of producing “evils that Congress has a right to prevent.” Although this may sound like a demanding test, Holmes applied it in a manner that seemed to permit speech to be censored whenever it endangered other social interests. Later that month, the Justices reached the same result in several other cases, including one involving the long-time socialist leader Eugene V. Debs.

It was no surprise, then, when the Court, in November, handed down a decision in Abrams v. United States upholding the convictions of four anarchists for advocating a strike by munitions workers. What was surprising was that in this case Holmes wrote a powerful and eloquent dissent, in which he argued that, under the First Amendment, we must be “eternally vigilant” to protect “the expression of opinions that we loathe and believe to be fraught with death,” on the ground that “free trade in ideas” is the best way to ascertain truth and thereby promote the good (Abrams, 630). Holmes reinterpreted Schenck's clear-and-present-danger test to permit restriction only when speech poses an imminent threat to the nation. Although his dissent was joined only by Justice Louis D. Brandeis, within a few decades it became the prevailing view, and it remains a landmark of modern First Amendment jurisprudence.

What led Holmes to change his mind so dramatically? That is the question that Thomas Healy explores in his deeply researched and highly engaging book, The Great Dissent. Healy shows that, although Holmes was partly responding to the growing repression of radical speech during this period, he was influenced most strongly by his interactions with Brandeis, Judge Learned Hand, and a circle of young progressives such as Harvard scholars Harold J. Laski, Felix Frankfurter, and Zechariah Chafee, Jr., all of whom urged him to take a more expansive view of free speech.

The general outlines of this picture are familiar from previous scholarship, such as Richard Polenberg's Fighting Faiths, but The Great Dissent adds a great deal of depth and color to the picture. Healy is especially insightful about Holmes's intellectual and personal relationships with his progressive friends, and the impact that they had on his views. The book does a masterful job of conjuring up the dilemma Holmes faced as he worked on Abrams: a struggle between his head, which told him that “persecution for the expression of opinions is [a] perfectly logical” way for the majority to pursue its goals (Abrams, 630), and his heart, which sympathized with his friends' devotion to intellectual freedom. Healy's extensive archival and legal research also yields several valuable nuggets of new information, including the origins of Holmes's famous remark in Schenck that “[t]he most stringent protection of free speech would not protect a man in falsely shouting fire in a theatre and causing a panic” (Schenck, 52).

The main weakness of The Great Dissent lies in the rather uncritical, celebratory attitude it takes toward Holmes's achievement in the Abrams dissent. That opinion has long had critics as well as admirers. Some scholars have objected that Holmes's position protects speech only when it is ineffective. Others have argued that Holmes's view has a dark side. In contrast to Brandeis, Holmes rejected any notion of the inherent value of individual liberty, human dignity, or democratic deliberation. Instead, his approach to law was rooted in a Darwinian belief that human life involves a struggle between competing groups. With this interpretation, Holmes came to see free speech not as a path toward a shared truth or the common good, but rather as an arena in which groups could struggle for dominance, a view he expressed 6 years later in Gitlow v. New York, in which he asserted that free speech was the best way to determine which beliefs were “destined to be accepted by the dominant forces of the community” (Gitlow, 673). From this critical perspective, Holmes's conception of the marketplace of ideas is a mixed blessing. Whereas it has led both the Court and the public to accept a broad commitment to free speech, it can also be seen to underlie decisions such as Citizens United v. Federal Election Commission (2010), which strike down efforts to prevent wealthy individuals and corporations from dominating the political process.

The Great Dissent would be even stronger if it subjected Holmes's Abrams dissent to the same thoughtful, critical evaluation that the book devotes to his earlier jurisprudence. On the whole, however, the book succeeds admirably in what it sets out to do: provide a comprehensive, vivid, and accessible account of how Holmes came to write an opinion that became “the foundational document of America's free speech tradition” (245).