Home » Perspective » New book explores John Stuart Mill’s influence on U.S. free speech protections

By John R. Vile, published on May 7, 2024

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"The Supreme Court and the Philosopher: How John Stuart Mill Shaped US Free Speech Protections" explores how Supreme Court interpretations of the free speech clause rely heavily and increasingly on John Stuart Mill (1806-1873), the 19th-century English utilitarian philosopher who authored “On Liberty.”

Review of Eric T. Kasper and Troy A. Kozma, The Supreme Court and the Philosopher: How John Stuart Mill Shaped US Free Speech Protections. Ithaca, NY: Northern Illinois University Press imprint of Cornell University Press, 2024.

Many discussions of and interpretations of the U.S. Constitution begin with American Founding Fathers. Discussions of the First Amendment, especially those that focus on the religion clauses, often cite James Madison and Thomas Jefferson and their efforts on the Virginia Statute for Religious Freedom. It is also common to interpret U.S. founding documents as embodying the philosophy of Britain’s John Locke or France’s Baron de Montesquieu

Eric T. Kasper and Troy A. Kozma are both professors at the University of Wisconsin-Eau Claire. Kasper is a professor of political science and Kozma is a professor of philosophy and department chair. In a fruitful collaboration, which reflects insights from both disciplines, they argue that Supreme Court interpretations of the free speech clause rely heavily and increasingly on John Stuart Mill (1806-1873), the 19th-century English utilitarian philosopher who authored “On Liberty.”

Book shows how justices have increasingly embodied Mill's thinking

As explained in the first chapter, Mill’s free speech philosophy was grounded on a libertarian no harm principle. Adults, no matter how contrarian, have broad rights to express themselves in a manner that does not cause harm to others. Only by exercising such freedoms can individuals reach their full potential. Moreover, even individuals who know the truth can refine their opinions and better understand their reasons for them by encountering opposing positions, even when such opinions are largely, if not completely, wrong.  

Subsequent chapters detail Supreme Court decisions on speech from a period preceding World War I through the current Roberts Court and show how the decisions have increasingly embodied Millian thinking. The  coverage of these cases is comprehensive and might even be a bit tedious for those who would prefer simply to know general trends. But the authors add some spice to the story both by highlighting how changes in thinking by individual justices as well as changes in court personnel led to current First Amendment doctrines. The authors laud time periods and justices who pointed the court in a more Millian direction and describe time periods and justices who accepted more encumbrances on free expression as being guilty of backsliding. 

They commend the decision in Brandenburg v. Ohio (1969), permitting speech that does not pose a threat of imminent lawless action as coming particularly close to Mills’ thinking on the subject. 

Authors: Connection to Mill dwarf any others in free speech case law

Although there is a difference between showing correlations between justices’ opinions and those of Mill and proving causation, the authors show fairly direct influences on some justices: 

  • Oliver Wendell Holmes Jr., who actually met with Mill in Europe (and was often allied with Justice Louis Brandeis on freedom of expression issues) and initially formulated the “clear and present danger test”; 
  • Chief Justice Charles Evans Hughes, who hung a portrait of Mill in his home office; and 
  • Justices, such as Hugo Black, who are known to have read Mill and frequently cited him in their opinions.  

The authors note that Mill was influenced by John Milton who defended  freedom of speech and press in “Areopagitia and whose work was almost certainly known by the American founders. The authors do not indicate, and this reviewer does not know, the degree to which Mill was familiar with and might have been influenced by any of the U.S. founders, or by other common sources such as John Locke’s “Letter Concerning Toleration,” or accounts of the trials of Peter Zenger in New York and John Wilkes in England.

Although the authors also acknowledge the influence of Locke, Alexis de Tocqueville, Zechariah Chafee, Alexander Meiklejohn, Thomas Emerson, and Burt Neuborne, they observe that “the connections to Mill outlined in this book dwarf the appeals to any other person in free expression caselaw, with only the First Amendment’s primary author, Madison, coming close” (p. 291). 

Authors could have more deeply explored founders' intentions

One obvious difference with Mill, which the authors mention but do not explore in great depth, is that many of the American founders grounded their ideas of First Amendment freedoms on the idea of natural rights (an idea clearly expressed in the Declaration of Independence). Mill based his philosophy on the utilitarian idea of the greatest happiness for the greatest number. The framers might arguably have placed First Amendment freedoms on a higher plane than either Mill or William Blackstone, who argued against licensing and prior restraint and supported blasphemy and other common law offenses that U.S. courts no longer recognize. 

Instead of accepting Millian influence as unproblematic, this reviewer wishes the authors had struggled a bit more with the implications for an interpretation of the formulation of American constitutional law not only through the eyes of someone who was not alive when the Constitution was drafted, but also from someone who was not even an American citizen. The authors seem convinced that Mill’s defense of freedom of expression remains the most complete or the most compelling available, but, with at least a bow to the idea of original intent, it would be helpful if the authors had explained the degree to which Mill’s philosophy was itself compatible or incompatible with the thought of those who drafted and ratified the free expression provisions in the First Amendment and the 14th Amendment through which the Supreme Court later applied the provisions to the states. Although the authors also portray Mill as a strong defender of religious liberties, comparison with the views of American founders on the subject might also have been useful.

That being said, there are few, if any, treatments of Supreme Court decisions on First Amendment freedoms of expression that are more comprehensive than this one, and it is a great resource for anyone seeking to understand these decisions and how they have been influenced by John Stuart Mill.

John R. Vile is a professor of political science and dean of the Honors College at Middle Tennessee State University.


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