Joel Jacobsen

In an interview, B.F. Skinner, the great apostle of American behaviorism, once summed up the basic concept of the criminal law.  Statutes, he said, are "statements of contingencies backed up by the political systems of the country."  He meant that laws control people's behavior by providing aversive stimuli:

An aversive stimulus is the opposite of a reinforcing stimulus, something we might find unpleasant or painful.

A behavior followed by an aversive stimulus results in a decreased probability of the behavior occurring in the future.

This both defines an aversive stimulus and describes the form of conditioning known as punishment.  If you shock a rat for doing x, it’ll do a lot less of x.  If you spank Johnny for throwing his toys he will throw his toys less and less (maybe).

(That's from a very useful online summary provided by Professor C. George Bouree.)

An ideal system of criminal justice -  I think this is intuitively obvious, but it's also in line with behaviorist theory - would combine a 100% chance of discovery/punishment with a graduated system of punishments:  conditional discharge (i.e., warning); probation; weekend jail sentence; jail; prison.  In such a world, the certainty that committing a crime would produce  an unpleasant or painful stimulus would ensure that only the incorrigible - the psychopaths - would ever need to be sent to prison.

Described like that, my ideal system of criminal justice sounds like a cage with levers in a psych dept laboratory, but I think normal human society ran pretty much along those lines for long stretches of our history.  In his early masterpiece The Pursuit of the Millennium, the late Norman Cohn wrote:

To an extent which can hardly be exaggerated, peasant life [in the Middle Ages] was shaped and sustained by customs and communal routine. ...  Social relationships within the village were regulated by norms which, though they varied from village to village, had always the sanction of tradition and were always regarded as inviolable. 

Familial relationships, of course, added another enmeshing network.  In such a society, it must have been very difficult to commit a violent crime secretly.   The near-certainty of discovery must have been a  powerful disincentive. 

A possible illustration of this point, from a different historical era, is provided by Jill Mocho's terrific Murder & Justice in Frontier New Mexico 1821-1846 . (1821-1846 was the interval between Mexico's independence and the American invasion.)  Mocho's researches uncovered just 11 homicide cases for that entire 25-year span.  Doubtless many other homicides escaped  the archives because the alcalde never found anyone to prosecute - but, if anything, that only proves the point.  Social isolation made villagers vulnerable to mobile strangers, but their social self-sufficiency protected them from themselves.

Also, such tightly-knit communities, with extended kinship structures, were not good laboratories for raising psychopaths.  Too much stability.  Too many other people involved in the child's life.  Too many positive role models.

But watch what happens in behaviorist theory if the risk of discovery/punishment slips much below 100%.  The association between committing a crime and the aversive stimulus is weakened, or even ceases to exist, so that being caught and punished seems less like an effect produced by the commission of the crime and more like a random stroke of bad luck.  A different kind of association is created:

B. F. Skinner’s entire system is based on operant conditioning.  The organism is in the process of “operating” on the environment, which in ordinary terms means it is bouncing around its world, doing what it does.  During this “operating,” the organism encounters a special kind of stimulus, called a reinforcing stimulus, or simply a reinforcer.  This special stimulus has the effect of increasing the operant -- that is, the behavior occurring just before the reinforcer.  This is operant conditioning:  “the behavior is followed by a consequence, and the nature of the consequence modifies the organisms tendency to repeat the behavior in the future.”

When the risk of being caught/punished is reduced, committing crime becomes associated with pleasure: the pleasure of power and dominance over others, the pleasure of sadism, or the various pleasures available to a person who has suddenly come into money. 

It's not hard to see that the two most significant trends in American criminal law for the past half-century have been directed toward (a) decreasing the probability of a guilty criminal being punished (that's the purpose of the numerous  non-textual exclusionary rules invented since the 1960s); and (b) increasing the severity of punishment.  We've been moving aggressively toward a society that is the photo negative (will that useful metaphor survive the disappearance of film?) of the ideal.

What's really interesting is that no one - well, no one who doesn't own stock in private prison companies - believes these are healthy trends.  Given that the criminal law itself is the preeminent example of behaviorist principles in action, how did we arrive at a system that contradicts basic behaviorist principles?  Ironically enough, it's because five justices of the Supreme Court thought it would be a spiffy idea to apply the principles of behaviorism to the criminal justice system.