San Diego Law Review


Gideon Yaffe

Document Type



In a variety of circumstances, it is justified to harm persons, or deprive them of liberty, in order to prevent them from doing something objectionable. We see this in interactions between individuals--think of self-defense or defense of others--and we see it in large-scale interactions among groups--think of preemptive measures taken by countries against conspiring terrorists, plotting dictators, or ambitious nations. We can argue, of course, about the details. Under exactly what conditions is it justified to inflict harm or deprive someone of liberty for reasons of prevention? But in having such arguments we agree on the fundamental idea: there are conditions under which prevention is justified, even if it is unclear precisely what those conditions are.

This Article aims to show that in a significant class of cases, the justificatory argument in favor of harming another in order to prevent that person from doing something objectionable is significantly weaker if that person's objectionable conduct is not imminent. This is so, it will be suggested, even if you are entirely certain that the person will do the objectionable thing if not prevented. Imminence is important to the justification of prevention, that is, independently of necessity. The argument for this controversial claim emerges from the discussion of the similarities between prevention and pre-punishment. Pre-punishment is wrongful, it is suggested, because the crime has not been actualized at the time of the punishment. A next best alternative to actualization is imminence. And so imminence aids in the justification of prevention for reasons closely related to the reasons why actualization is needed for the justification of punishment.

Part II concerns pre-punishment and identifies the sense in which punishment's justification depends on the actuality of the crime for which punishment is issued. The Part also justifies this actuality requirement on punishment through appeal to a necessary condition on desert of punishment?one found, among other places, in the writings of Samuel Pufendorf. Part III explains the sense in which imminence can serve not as a replacement for actuality but as a next-best alternative that allows for the justification of a certain class of preventions, namely, those in which part of what justifies the act of prevention is that the person thereby harmed would have deserved such harm had that person gone through with the objectionable act that the harm prevented. The Part also explains why imminence is of independent importance from necessity. The conclusion of the Article solves the two puzzles about the relationship between prevention and pre-punishment by drawing on the conceptual resources developed in the preceding Parts.