George Thomas's The (Un)Written Constitution begins with the observation that there is a startling disconnect between how some conservative judges and justices speak in public about what they do—we stick to the plain text of the constitution!—and what they actually do in practice, which is rely on principles, theories, and structural insights to animate and interpret ambiguous constitutional text.

As Thomas himself notes, this observation is “hardly news” (5) to scholars and practitioners familiar with the debate. When speaking with fellow elites, conservative academics and jurists describe originalism in a more nuanced manner, as an interpretive approach that deploys text, structure, and history to decide constitutional questions. The project of The (Un)Written Constitution is to illustrate this disconnect between elite and public discourse around originalism by showing how it plays out in certain Supreme Court opinions. In doing so, Thomas adds texture and depth to the conversation around originalism by teasing out the unwritten ideas, principles, and “political theor[ies]” (6) that undergird these landmark decisions.

The (Un)Written Constitution is organized into five chapters sandwiched between an introduction and a conclusion. Instead of proceeding chronologically, each chapter, indeed each subsection, is structured by the logic of the unwritten ideas Thomas is discussing. For example, in chapter 4 (“Text and the Separation of Powers”) Thomas starts with a 1988 case about the constitutionality of the Independent Counsel provision of the Ethics in Government Act (83–89), rewinds to debates surrounding the removal power from 1789 (90–94), fast forwards again “over 200-plus years” to a 2010 case implicating the Sarbanes-Oxley Act (94–97), then rewinds back to the Korean War and the Steel Seizure case (97–100). From there the analysis moves forward again to a 2004 Guantanamo Bay detainee case (100–105), then concludes with a discussion of President Washington and Alexander Hamilton's views on the executive power from 1793 (105–8).

While dizzying at times, Thomas's ideas-driven approach has the benefit of taking the reader on a fascinating journey back and forth through time in order to draw connections across time. However, one casualty of this approach can be the flattening out of political and historical contexts that, for a political scientist or a legal historian, are crucial to understanding and explaining how and why these particular unwritten ideas became useful or attractive to Supreme Court justices at these particular times.

In terms of its audience, The (Un)written Constitution is not aimed at scholars or legal practitioners who are already elbows deep in the conversation over constitutional interpretation and development. Thomas does pepper in citations to some of the scholarly literature on the topics, but the book does not engage seriously with it, nor does it pretend to. The (Un)Written Constitution is also too deep in the weeds with its constitutional analysis to be aimed at a public or generalist audience. In his analyses, Thomas assumes a significant amount of background knowledge and understanding of the Supreme Court and constitutional law. Instead, The (Un)Written Constitution reads like it was written as a supplement to a standard two-course constitutional law sequence and I think it would be best adopted as such.

For example, I can imagine students of Con Law I appreciating Thomas's in-depth analysis of the principles and political theory animating Justice Scalia's dissent in the separation of powers case Morrison v. Olson (84–97). Similarly, students of Con Law II will find Thomas's deep dive into the conservative critique of substantive due process in chapter 2 (38–42) especially important as a conservative supermajority on the Supreme Court has begun to unravel the foundations of that doctrine with their decision in Dobbs v. Jackson Women's Health Organization (597 U.S. ___ 2022).

I found myself with a number of unanswered, bigger-picture “why” questions as I wrapped up The (Un)Written Constitution. As I noted, Thomas takes as his jumping-off point the disconnect between “the public face” of originalism and the actual practice of originalism (5). Indeed, after reading this book, one cannot help but wonder how anyone could believe the myth that all judges and justices do is stick to “the precise text” of the constitution (143). So, why do conservative judges and Republican politicians perpetuate this myth? In whose interest is it? I think the answer to that question would have to start from an understanding of mass political behavior, political parties—and the different organizing logics between Democrats and Republicans—and the changing nature of judicial appointments, constitutional hardball, and the role of the Senate confirmation hearings. This kind of analysis would have been a welcome epilogue to The (Un)Written Constitution.

This leads me to my second big-picture question: Where is politics in all of this? As far as I can tell, the first time politics enters the conversation in The (Un)Written Constitution is in the conclusion, as Thomas reminds “us” (that is, citizens of the United States) that our real power is to vote for elected representatives who hold the same ideas and values about the constitution as we do (33). While I appreciate this civic reminder, as a political scientist, I found myself waiting for Thomas to connect the dots between the unwritten ideas he analyzes, the politics of the judges who espouse them, and the politicians and interest groups and parties who benefit from them. Thomas starts to get there, again in the conclusion when he discusses the Republican-controlled Roberts Court's partisan gerrymandering decisions—justified by the unwritten, judge-invented idea of the “political questions doctrine”—as having the practical effect of benefiting the Republican Party (132–35). I was looking for more of this kind of transparency around who benefits from the often-strategic deployment of competing understandings of The (Un)Written Constitution over time.

I say all this not to be dismissive of Thomas's contribution in The (Un)Written Constitution. As I said, I think this book will be an excellent supplement for students working their way through the canon of constitutional law and trying to understand why and how the constitution and its meaning evolve over time, even when the text does not change. In my experience, the best reads are the ones that leave us with burning questions for future scholars and thinkers to resolve. The (Un)Written Constitution certainly accomplishes that.