The Preventive State: The Challenge of Preventing Serious Harms While Preserving Essential Liberties

by Alan M. Dershowitz

Rarely in the long history of our planet, have we faced such dire threats to our nuclear annihilation, out of control pandemics, international terrorism, environmental disasters, racial and ethnic divisions, challenges to the rule of law, attacks on basic liberties including speech and due process, health care policies (or lack thereof) that create disparate life expectancies based on race and nationality, rampant crime, police misconduct, school and other mass shootings and additional dangers. But rarely in our history have we developed tools so capable of predicting and preventing many of these potential disasters. It is the combination of these two phenomena — increasing dangers coupled with increasing capabilities by governments (often aided by private technology) to prevent them— that has given rise to the preventive state. The Preventative State shows how, all in all, the “tragic choices,” of evils, or even of goods with some negative consequences – decisions that involve high costs on both sides – are similar in many predictive-preventive decisions, whether they involve big government, big tech, big medicine, big pharma, big education, big media or any other large-scale institutions that affect the lives of people. There are, to be sure, real differences in kind and degree, depending on the nature and function of the institutions, but the similarities and analogies help inform thoughtful consideration of options and may provide insights into any effort to construct a jurisprudence of prevention based on predictions of harm.

Genres: Politics, Nonfiction

240 pages, Hardcover

Published May 20, 2025

About the author

Alan Morton Dershowitz is an American lawyer, jurist, and political commentator. He is the Felix Frankfurter Professor of Law at Harvard Law School. He is known for his career as an attorney in several high-profile law cases and commentary on the Arab-Israeli conflict.

He has spent most of his career at Harvard, where, at the age of 28, he became the youngest full professor in its history, until Noam Elkies took the record. Dershowitz still holds the record as the youngest person to become a professor of law there.

As a criminal appellate lawyer, Dershowitz has won thirteen out of the fifteen murder and attempted murder cases he has handled. He successfully argued to overturn the conviction of Claus von Bülow for the attempted murder of Bülow's wife, Sunny. Dershowitz was the appellate advisor for the defense in the criminal trial of O.J. Simpson for the murder of his ex-wife Nicole Simpson and her friend Ronald Goldman.

Reviews

[Clay Davis · Rating 4 out of 5]

This work brings to the forefront the legal challenges that require the wisdom of Solomon.

[Science and Fiction · Rating 5 out of 5]

This is an excellent book organized into small chapters by talking point and presented with clarity so that those outside of the field can readily understand the concepts of the law. There are chapters on preventing terrorism, preventative medical intrusion, free speech vs. hate speech, gun laws, the surveillance state, and much more. Along the way Dershowitz gives gentle admonishment to those of inflexible positions on the far Left and far Right saying that “prevention as a general matter should not divide along partisan lines.” There may be grumbles from those whose ideology does not allow a centrist position, and some grumbling is to be expected when people don’t get everything they want, as long as citizens understand the overall value to society in having clarity and transparency on these issues.

To make his overarching case, which rides throughout the whole book, Dershowitz first explains how there is a matrix of four possible options in any preventative decision: true positive, false positive, true negative, and false negative. It will be important to understand this right away as it keeps coming back and underlies the logic of the proposed framework he later presents. As an example he cites Pascal’s Wager, which in times past was used by theologians to advocate Christian doctrine: a true positive is when belief in God results in eternal heavenly reward, a false positive is a belief in God which turns out to be unfounded, and true negative is a disbelief in God which turns out to be correct, and a false negative is a disbelief in God which is proven to be incorrect. In such a case, two of the outcomes have significant impact: either eternal reward in Heaven, or eternal torment in Hell. Those of non-Christian persuasion drop the hellish consequence and simply use the argument as a cost-benefit analysis between potential for big reward vs. ‘nothing lost.’

Dershowitz goes on to say that most cases only have one significant issue with the other three being relatively benign. The balancing act has always been how to mitigate against catastrophic outcomes to society as a whole while minimizing the restrictions of freedoms of individual citizens.

Dershowitz makes some important distinctions which I hadn’t considered before, such as those ideas which are specifically protected by the constitution versus those that may be more subject to the changing landscape of political whim. For example, the difference between the FDA in saying which foods are safe or not safe for consumption, versus the idea of free speech. “The court thus struck different constitutional balances between false positives and false negatives when it came to food [FDA], which is not constitutionally protected, and books, which are.” Dershowitz also says “Freedom of speech entails a degree of risk. So does censorship. We must balance those risks in a manner that favors speech over fear. In the absence of convincing evidence of significant harm, censorship – especially prior restraint – must not be permitted.”

I was also made more aware of the trade-offs between having a sluggish and inefficient bureaucratic state versus off-loading these services to private business, and the answer is that state-run services have traditionally been subject to constitutional scrutiny, while private business is given a longer leash. The trade-offs are vigorously argued and corresponds to the ongoing debate as to which is worse: Big Brother or Big Business. Dershowitz gives examples of how both can be problematic. I’m most concerned about Big Business having access to DNA results in order to increase premiums or deny coverage for individuals based on hereditary potentialities. This is why we need a preventative framework that should be debated amongst the bicameral legislators so that law enforcement and the judiciary don’t have to re-invent the wheel with each and every case.

I didn’t agree with Dershowitz on every particular, but, as Dershowitz says again and again, these are details which need to be worked out by democratic process in Congress.

This book seems to represent a well-considered culmination of Dershowitz’ sixty-five years in teaching, writing books, courtroom experience, and testifying before Congress. It probably wouldn’t hurt to send a copy of the book to your elected representative. They are the ones who really need to read the book!

[Gay · Rating 1 out of 5]

Dershowitz can no longer be believed. Great mind went the way of Rudy G. Dershowitz neglects to discuss the serious harms caused by ignoring the constitution and a politicized Supreme Court that now only agrees with hard core right wing regimes and has dismantled rule of law.

Dershowitz doesn't have a chapter on preventing serious harms when our country is run at the top by threatening others for personal gain without any checks and balances.

There is ZERO discussion on why 3 EQUAL branches of gov are so important in preventing harms and maintaining our constitution.

[Jack · Rating 3 out of 5]

legal theory is divorced fro common sense.

I know my headline is silly, but it rings true to me. Whenever I read a court decision or a book like this it seems like a discussion about how many angels can dance on the he’d of a pin. It’s all about co-opting language to meet your objectives. We need laws, but lawyers who are just wordsmiths cause more problems than they solve. I like listening to Dershowitz’s podcasts, but this book is kinda boring

[Daisy S. · Rating 2 out of 5]

I like his premise but it didn’t feel like he was coming to any conclusions, personal opinions or recommendations other than saying that we need a legal framework for this. He didn’t raise any moral dilemmas that the average educated reader wouldn’t have already thought about if the reader was drawn to the book in the first place. Like so much non-fiction written by today’s publishing intellectuals, it would have been a better magazine article and did not have enough content for a full book.