Great Performance !

The evidence linking increased punishment with lower crime rates is very strong. Harsh prison terms have been shown to act as both deterrent (for the would-be criminal on the street) and prophylactic (for the would-be criminal who is already locked up). Logical as this may sound, some criminologists have fought the logic. A 1977 academic study called “On Behalf of a Moratorium on Prison Construction” noted that crime rates tend to be high when imprisonment rates are high, and concluded that crime would fall if imprisonment rates could only be lowered. (Fortunately, jailers did not suddenly turn loose their wards and sit back waiting for crime to fall. As the political scientist John J. DiIulio Jr. later commented, “Apparently, it takes a Ph.D. in criminology to doubt that keeping dangerous criminals incarcerated cuts crime.”) The “Moratorium” argument rests on a fundamental
confusion of correlation and causality. Consider a parallel argument. The mayor of a city sees that his citizens celebrate wildly when their team wins the World Series. He is intrigued by this correlation
but, like the “Moratorium” author, fails to see the direction in which the correlation runs. So the following year, the mayor decrees that his citizens start celebrating the World Series before the first pitch is thrown—an act that, in his confused mind, will ensure a victory.

There are certainly plenty of reasons to dislike the huge surge in the prison population. Not everyone is pleased that such a significant fraction of Americans, especially black Americans, live behind bars. Nor does prison even begin to address the root causes of crime, which are diverse and complex. Lastly, prison is hardly a cheap solution: it costs about $25,000 a year to keep someone incarcerated. But if the goal here is to explain the drop in crime in the 1990s, imprisonment is certainly one of the key answers. It accounts for roughly one-third of the drop in crime.

Another crime-drop explanation is often cited in tandem with imprisonment: the increased use of capital punishment. The number of executions in the United States quadrupled between the 1980s and the 1990s, leading many people to conclude—in the context of a debate that has been going on for decades—that capital punishment helped drive down crime. Lost in the debate, however, are two important facts.

Taken From : A Rogue Economist Explores the Hidden Side of Everything