The Penumbra Problem - by Jared Schroeder (Hardcover)

Book Synopsis

The U.S. Constitution is silent about a right to privacy, yet the Supreme Court determined in the 1965 reproductive rights case Griswold v. Connecticut, that such a right is inferred from the Bill of Rights. The reasoning in the landmark case hinged on an unexpected word--penumbra. The Court concluded, in other words, that the unmentioned right to privacy resides in the shadows of the amendments.

But this was not the first time penumbral imagery was used in legal writings, and its broader cultural usage dates back much further. Jared Schroeder's The Penumbra Problem provides a much-needed--and quite colorful--social and cultural history of the term. The penumbra concept, it turns out, wasn't an accidental choice but instead a well-selected term with centuries of transnational history.

Schroeder tells its story through two intertwining narratives: first, how the word penumbra transcended its oblique scientific origins to become a distinct cultural concept; and, second, the parallel story of its evolving use in legal thought. The book tracks back and forth in time, creating an unexpected lineage of people and works who became unwitting champions of the penumbra concept, including mathematician Johannes Kepler, feminist activist Estelle Griswold, British thinker Robert Hooke, and lexicographer Noah Webster. Pairing these stories with the writings of great legal thinkers such as Willam Douglas and Oliver Wendell Holmes, Schroeder is able to construct a kind of etymological love letter to this obscure concept.

Not everyone has supported the privacy precedent, though, and it is no exaggeration to say that it is in danger today. Schroeder's clever, utterly unique history is, at its core, a call to redouble efforts to save the right to privacy. He argues that we must understand its ponderous, indeed uncertain, origins to fully appreciate the precarity in which it exists today, and only then can we adequately fight for it.

Review Quotes

"In a thought-provoking and exhaustively researched exploration into the singular concept that underlies Americans' right to privacy, Jared Schroeder makes a compelling argument that the historical provenance behind the Constitution's penumbral protections has been ignored for far too long, including by the Supreme Court's Originalists who seek to assail it." --Amy Kristin Sanders, Penn State University

"Jared Schroeder has taken one word from a Supreme Court opinion - penumbra - and written a beautiful, timely, and vital book about its role in shaping our constitutional right to privacy. With a historian's attention to detail and razor-sharp legal analysis, Schroeder pushes back on attacks of the penumbra concept and explains why it matters now more than ever."--Jeff Kosseff, author of The Twenty-Six Words That Created the Internet

"Jared Schroeder offers a deep dive into the under-explored constitutional concept of penumbra and its significant influence on how privacy rights have been interpreted in the United States. Along with providing historical, social, and legal context, this book delivers a set of promising solutions for how we might reclaim the concept and our claims to constitutional privacy."--Jasmine McNealy, University of Florida

About the Author

Jared Schroeder is Professor and Lee Hills Endowed Chair in Free-Press Studies at the University of Missouri School of Journalism. He is the author of three books, most recently The Structure of Ideas (SUP, 2024). His journalism has been published by Overby Center,, and Slate.