Elsevier

Economics Letters

Volume 107, Issue 2, May 2010, Pages 205-207
Economics Letters

A model of criminal sanctions that incorporate both deterrence and incapacitation

https://doi.org/10.1016/j.econlet.2010.01.025Get rights and content

Abstract

This paper adapts the standard economic model of crime to incorporate both deterrence and incapacitation. The results show that adding incapacitation can result in either a longer or a shorter optimal prison term compared to the deterrence-only model.

Introduction

Economic models of law enforcement since Becker (1968) have focused primarily on the goal of deterrence (see, e.g., the surveys by Polinsky and Shavell, 2000, Polinsky and Shavell, 2007). Much less attention has been paid to the incapacitation function of imprisonment (exceptions are Ehrlich, 1981, Shavell, 1987). Yet actual law enforcement policies almost certainly combine both motives for punishment, as reflected by the seeming “overuse” of prison from the perspective of deterrence models, which prescribe the use of fines up to the limit of a defendant's wealth before imposing prison time. Recent three-strikes laws, which imprison an offender for life on a third offense, are an example.

The purpose of this note is to develop an economic model of law enforcement that combines the deterrence and incapacitation motives for punishment. Analytically, this requires adding a dynamic element to the standard Becker–Polinsky–Shavell (BPS) deterrence model, which typically treats the potential offender's decision of whether or not to commit a crime as one-time. In contrast, incapacitation envisions some offenders as being habitual (undeterrable) in the sense that they commit repeated crimes whenever free, irrespective of the threat of punishment. In the hybrid model, offenders are infinitely lived and potentially commit crimes throughout their lives, but they may also be deterred by the threat of punishment. In this setting, prison potentially serves the dual functions of deterring some offenders from ever committing crimes and incapacitating those who do.

Section snippets

The model

Assume that potential offenders have infinite life spans. At time zero, they each take a random draw of the monetary gain from committing a crime, g, which is distributed by the density function z(g). Each offender's realized g will remain his “type” throughout his life (thus, each offender will make the same choice each time he is confronted with a criminal opportunity). Time is continuous, and g is therefore defined to be the gain per instant of time that an offender is free and committing

Conclusion

This paper has developed a unified model that incorporates the motives of deterrence and incapacitation. This exercise is desirable from the perspective of the positive economic theory of law since there seems little doubt that both motives operate in the design of actual criminal policy. The results of the hybrid model showed that the inclusion of incapacitation may either lengthen or shorten the optimal prison term compared to the pure deterrence model; it lengthens the prison term if there

Acknowledgement

I appreciate the comments of an anonymous referee.

References (7)

  • G. Becker

    Crime and punishment: an economic approach

    Journal of Political Economy

    (1968)
  • M. Davis

    Time and punishment: an intertemporal model of crime

    Journal of Political Economy

    (1988)
  • I. Ehrlich

    On the usefulness of controlling individuals: an economic analysis of rehabilitation, incapacitation and deterrence

    American Economic Review

    (1981)
There are more references available in the full text version of this article.

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