FOR MOST of this century, the American justice system has relied on one of three general models of punishment. Liberals have argued for rehabilitation: Lock up the criminals, teach them the good life, mold them into law-abiding citizens and then let them go. But most studies indicate that such programs do not reduce reoffense rates. Conservatives have argued for incapacitation: Lock up criminals so they can't get out to commit more crimes. But a consensus seems to be developing that even if we could catch and imprison enough criminals to reduce crime substantially, the cost -- even for the wealthiest of countries -- would be prohibitive. Finally, partisans on both sides have argued that sentences should be handed down that will deter both the individuals convicted -- specific deterrence -- and others in society who observe the punishment -- general deterrence. But the studies and scholarly literature on deterrence are not convincing in this regard.

Meanwhile, the long-dominant theory that people commit crimes after weighing benefits and liabilities and coming to a rational conclusion has also been called into question. The idea that people don't engage in a calculus of punishment to determine whether or not to commit crime was supported by a recent study by Tom Tyler, a professor of psychology at Northwestern University. Researchers interviewed 1,575 Chicagoans about their attitudes toward police and courts and about their level of compliance with various laws. Tyler's and other researchers' findings directly contradict the widely held assumption that people are motivated by self-interest, that they obey the law because they fear punishment. The people Tyler studied did not "react to their experiences or behave in a way that can be easily explained by reference to their short-term self-interest." Instead, people obey the law because they believe it is proper to do so. They obey the law if it is legitimate and moral and they accept decisions if they are fairly arrived at.

Similarly, Australian theorists John Braithwaite and Philip Pettit argue that people comply with the law most of the time not because they fear punishment but because "criminal behavior is simply abhorrent to them." Law-abiding persons, they write, "engage in no rational weighing of the costs and benefits of crime before deciding whether to comply with the law." Instead, they act out of aversion to shame, which "is critical to understanding why most serious crime is unthinkable to most of us."