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Book Excerpt: 'Preemption'

'Preemption: a Knife That Cuts Both Ways'

The democratic world is experiencing a fundamental shift in its approach to controlling harmful conduct. We are moving away from our traditional reliance on deterrent and reactive approaches and toward more preventive and proactive approaches. This shift has enormous implications for civil liberties, human rights, criminal justice, national security and foreign policy -- implications that are not being sufficiently considered. It is a conceptual shift in emphasis from a theory of deterrence to a theory of prevention, a shift that carries enormous implications for how society controls dangerous human behavior, ranging from targeted killings of terrorists, to preemptive attacks against nuclear and other weapons of mass destruction, to preventive warfare, to proactive crime prevention techniques (stings, informers, wiretaps), to psychiatric or chemical methods of preventing sexual predation, to racial, ethnic, or other forms of profiling, to inoculation or quarantine for infectious diseases (whether transmitted "naturally" or by "weaponization"), to prior restraints on dangerous or offensive speech, to the use of torture (or other extraordinary measures) as a means of gathering intelligence deemed necessary to prevent imminent acts of terrorism.

Although the seeds of this change were planted long ago and have blossomed gradually over the years, it was the terrorist attack against the United States on September 11, 2001, that expedited and, in the minds of many, legitimated this important development. Following that attack, the former attorney general John Ashcroft described the "number one priority" of the Justice Department as "prevention." The prevention of future crimes, especially terrorism, is now regarded as even "more important than prosecution" for past crimes, according to the Justice Department. In his confirmation hearings of January 5, 2005, Attorney General Alberto Gonzales reiterated that the administration's "top priority is to prevent terror attacks." The tactics that have been employed as part of this preventive approach include tighter border controls, profiling, preventive detention, the gathering of preventive intelligence through rough interrogation and more expansive surveillance, targeting of potential terrorists for assassination, preemptive attacks on terrorist bases, and full-scale preventive war. We are doing all this and more without a firm basis in law, jurisprudence, or morality, though there certainly are historical precedents -- many questionable -- for preventive action.


The shift from responding to past events to preventing future harms is part of one of the most significant, but unnoticed, trends in the world today. It challenges our traditional reliance on a model of human behavior that presupposes a rational person capable of being deterred by the threat of punishment. The classic theory of deterrence presupposes a calculating evildoer who can evaluate the cost-benefits of proposed actions and will act -- and forbear from acting -- on the basis of these calculations. It also presupposes society's ability (and willingness) to withstand the lows we seek to deter and to use the visible punishment of those blows as threats capable of deterring future harms. These assumptions are now being widely questioned as the threat of weapons of mass destruction in the hands of suicide terrorists becomes more realistic and as our ability to deter such harms by classical rational cost-benefit threats and promises becomes less realistic.

Among the most frightening sources of danger today are religious zealots whose actions are motivated as much by "other-worldly" costs and benefits as by the sorts of punishments and rewards that we are capable of threatening or offering. The paradigm is the suicide terrorist, such as the ones who attacked us on September 11th. We have no morally acceptable way of deterring those willing to die for their cause, who are promised rewards in the world to come. Recall the serene looks on the faces of the suicide terrorists as they were videotaped passing through airport security in the final hours of their lives. It is not that they are incapable of making "rational" cost-benefit calculations, by their own lights. But these calculations involve benefits that we cannot confer (eternity in paradise) and costs (death) that to them are outweighed by the expected benefits. They are in some respects like "insane" criminals who believe that God or the devil told them to do it. Because they are not deterrable, the argument for taking preventive measures against them becomes more compelling. Blackstone made this point in the context of "madmen": "As they are not answerable for their actions, they should not be permitted the liberty of acting..." Nations whose leaders genuinely -- as opposed to tactically -- believe that their mission has been ordained by God (such as today's Iran) may also be more difficult to deter than those who base their calculations on earthly costs and benefits (such as today's North Korea or Cuba).


The classic theory of deterrence contemplates the state absorbing the first harm, apprehending its perpetrator and then punishing him publicly and proportionally, so as to show potential future harm doers that it does not pay to commit the harm. … In the classic situation, the harm may be a single murder or robbery that, tragic as it may be to its victim and his family, the society is able to absorb. In the current situation the harm may be a terrorist attack with thousands of victims, or even an attack with weapons of mass destruction capable of killing tens of thousands. National leaders capable of preventing such mass attacks will be tempted to take pre-emptive action, as some strategists apparently were during the early days of the Cold War.


One of the great difficulties of evaluating the comparative advantages and disadvantages of deterrence versus preemption is that once we have taken preemptive action, it is almost never possible to know whether deterrence would have worked as well or better. It is also difficult to know with precision the nature and degree of the harm that may have been prevented. Moreover, at the time the decision has to be made -- whether to wait and see if deterrence will work or whether to act preemptively now -- the available information will likely be probabilistic and uncertain. It is also difficult to know with precision the nature and degree of the harm that may have been prevented. For example, if a preemptive attack on the German war machine had succeeded in preventing World War II, we would never know the enormity of the evil it prevented. All that history would remember would be an unprovoked aggression by Britain on a weak Germany.


The conundrum, writ large, may involve war and peace. Writ small it may involve the decision whether to preventively incarcerate an individual who is thought to pose a high degree of likelihood that he will kill, rape, assault, or engage in an act of terrorism. At an intermediate level, it may involve the decision to quarantine dozens, or hundreds, of people, some of whom may be carrying a transmittable virus like SARS. At yet another level, it may raise the question of whether to impose prior restraint on a magazine, newspaper, television network or internet provider that is planning to publish information that may pose an imminent danger to the safety of our troops, our spies or potential victims of aggression. Since the introduction of the internet -- which, unlike responsible media outlets, has no "publisher" who can be held accountable after-the-fact -- there has been more consideration of before-the-fact censorship.

At every level, preventive decisions must be based on uncertain predictions, which will rarely be anywhere close to 100 percent accurate. We must be prepared to accept some false positives (predictions of harms that would not have occurred) in order to prevent some true positives (predictions of harm that would have occurred had we not intervened) from causing irreparable damage. The policy decisions that must be made involve the acceptable ratios of inevitable errors in differing contexts.

Over the millennia we have constructed a carefully balanced jurisprudence of after-the-fact reaction to harms, especially crimes. We have even come to accept a widely agreed upon calculus: "better 10 guilty go free than even one innocent be wrongly convicted." Should a similar calculus govern preventative decisions? If so, how should it be articulated? Is it better for 10 possibly preventable terrorist attacks to occur than for one suspected, possibly innocent, terrorist to be preventively detained? Should the answer depend on the nature of the predicted harm? The conditions and duration of detention? The past record of the detainee? The substantive criteria employed in the preventive decision? The ratio of true positives to false positives and false negatives? These are the sorts of questions we will have to confront as we shift toward more preventative approaches -- whether it be terrorism, crime in general, the spread of contagious diseases or preventive warfare.


The current focus on pre-emption, resulting from the political debate over particular pre-emptive policies and actions, now affords me an opportunity to bring my thinking, teaching and writing together into a short book. In this book, I will propose some generalizations about pre-emption in its varying contexts and manifestations and suggest how a democratic society might begin to construct a jurisprudence -- a philosophy -- of pre-emption. Put another way, I will try to articulate the factors that should go into any process of striking the proper balances between the virtues and vices of early intervention, especially when the intervention involves the use of force, power, compulsion, censorship, incarceration and death, and most especially when the failure to intervene may also involve comparable threats, dangers and harms. When the stakes are so high and when the available options tend to be "tragic choices" or "choices of evils," the need for thoughtful, calibrated and nuanced analysis become even more compelling. The question "are you for or against pre-emption" thus becomes exposed as a meaningless polemic, as empty of content as the question "are you for or against deterrence" or "are you for or against punishment?" The costs and benefits of each category of preemptive or preventive decision -- indeed of a specific decision -- must be carefully weighed and openly debated. I hope to stimulate such debate with this book.

Excerpted from Preemption: A Knife That Cuts Both Ways Copyright © 2006 by Alan M. Dershowitz.

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Alan Dershowitz