A society can be thought of as a collection of private and public systems. At present a number of these systems in American society are under stress: the medical system, the educational system (other than elite private schooling and elite university education), the political system (especially at the legislative level), the finance industry, the fiscal system (including taxation, borrowing, and spending at all levels of government), transportation infrastructure, the regulation and assimilation of immigrants, and perhaps others. In contrast, foreign affairs, the military (and national security generally), and industries such as retailing, the production of intellectual property, computer technology, and the production of pharmaceuticals and medical technology are areas of great national strength.
Another troubled American system is that of criminal justice, with particular emphasis on the astrounding growth and level of imprisonment. Some statistics: the incarceration rate had been 118 per 100,000 in 1950, and actually fell in 1972 to 93 per 100,00. By 2000 it had reached 469 and only since the advent of the economic crisis has it begun to decline as states try to reduce expenditures. Between 1950 and 2000 the white imprisonment rate increased by 184 percent and the black imprisonment rate by 355 percent; today 40 percent of prison and jail inmates are black, although blacks are only 13 percent of the overall population. Even though the U.S. crime rate fell by a third in the 1990s (and by two-thirds in many large cities)— the murder rate by more than 40 percent—the inmate population continued growing during this period, an increase that cannot be explained by population growth, since the population grew by much less than a third in the 1990s.
The inmate population started its rapid growth in the early 1970s, largely in response to sharply rising crimes rates in the 1960s, a decade of domestic unrest. In 1960 the homicide rate was 4.6 per 100,000 persons; in 1970, 7.9; in 1980, 10.2; in 1990, 9.4—but by 2000 it had dropped 5.5 and it is about the same today, which is to say that it is almost back to where it was in 1960, before crime became a big issue. Crime rates are higher than they were in the 1950s but they are tolerable, yet the incarcerated percentage of the population remains much higher now than then.
The economist Steven Levitt, after correcting for other factors that have been proposed as explanations for the decline in crime rates since 1980, has attributed the leveling of and then decline in those rates to the increase in the prison population, along with increases in the number of police, a decline (largely, it seems, independently of law enforcement) in the consumption of crack cocaine, and the legalization of abortion in the early 1970s. Legalization resulted (Levitt argues, though his statistical evidence has been questioned) in a decline in crime rates twenty years later; unwanted children are more likely to be neglected, brought up badly, and as a result get into trouble as young adults than wanted children.
The striking thing is that although the criminal sentences are considerably more severe in the United States than in our peer countries, which one expect to have a substantial deterrent effect, the percentage of the American population that is incarcerated is the highest of any country in the world—at 2.3 million, it is about .8 percent (eight-tenths of 1 percent), which is 4 to 7 times the percentage of any of our peer countries—and our crime rates are generally no lower than in those countries and our murder rate is much higher. Although we have a larger black population than those countries, and our blacks are disproportionately engaged in crime, as noted earlier, even if their crime rate were no higher than that of the rest of the population our overall crime rate would still greatly exceed that of the other countries, because it would fall by only 27 percent from its present level, or to about 1.8 million, which is .6 percent of the population, compared to its current level of.8 percent.
Long prison sentences should deter crime, or if not deter then incapacitate the criminals and thus prevent them from committing crimes (outside the prison itself) for a long period of time. We might therefore expect to have lower crime rates than our peer countries, and, given the deterrent effect of heavy sentences, lower rates of imprisonment. The fact that instead the U.S. imprison more persons in prison than foreign countries do, yet has no lower a crime rate, calls for explanation. If the demand for crime in the U.S. were no higher than in those countries, and the supply price no lower, we would expect the the United States to have a lower crime rate if it imprisons more persons. So the fact that our crime rate isn't lower requires investigation. The investigation might show for example that we criminalize more activity, which is the equivalent of increasing the demand for crime. If an activity is criminalized, this increases the amount of crime unless the criminalization of the activity drives its level to zero.
There are a number of other possible explanations for the conjunction of a high rate of imprisonment with a high crime rate. One is not enough police, or intelligent enough police, to prevent and detect crime effectively. Another is a high elasticity of supply for criminal activity, so that discouraging or preventing one person from committing crimes induces someone else to enter the crime industry. Another (suggested above) is that we define crime too broadly, criminalizing activities that in other countries are lawful; our high rate of sexual offenses against minors is a function in part of a high age of consent (18). Or we may make too little use of fines, and of regulatory and private-litigation alternatives to criminal punishment. The prevalence of gun ownership may be a factor, along with the proximity to the United States of countries in Latin America that are large producers of illegal drugs. And finally crime rates are particularly high in the southern states of the United States, and that may have deep cultural roots.
Reform is difficult when the causes of a problem are multiple or unknown. And because the direct monetary costs of the criminal justice system are not very great by current standards (only about $40 billion a year), and there is strong hostility among the general public to criminals (another cultural fact, perhaps), and because our huge prison system provides a great deal of employment, there is no pressure for reform. Yet the indirect costs of high levels of incarceration must be very great, in the form of the lost output of the large number of prisoners, most of whom are of working age.