Freakonomics Revised and Expanded Edition

by Steven D. Levitt

  First, given the rarity with which executions are carried out in this country and the long delays in doing so, no reasonable criminal should be deterred by the threat of execution. Even though capital punishment quadrupled within a decade, there were still only 478 executions in the entire United States during the 1990s. Any parent who has ever said to a recalcitrant child, “Okay, I’m going to count to ten and this time I’m really going to punish you,” knows the difference between deterrent and empty threat. New York State, for instance, has not as of this writing executed a single criminal since reinstituting its death penalty in 1995. Even among prisoners on death row, the annual execution rate is only 2 percent—compared with the 7 percent annual chance of dying faced by a member of the Black Gangster Disciple Nation crack gang. If life on death row is safer than life on the streets, it’s hard to believe that the fear of execution is a driving force in a criminal’s calculus. Like the $3 fine for late-arriving parents at the Israeli day-care centers, the negative incentive of capital punishment simply isn’t serious enough for a criminal to change his behavior.

  The second flaw in the capital punishment argument is even more obvious. Assume for a moment that the death penalty is a deterrent. How much crime does it actually deter? The economist Isaac Ehrlich, in an oft-cited 1975 paper, put forth an estimate that is generally considered optimistic: executing 1 criminal translates into 7 fewer homicides that the criminal might have committed. Now do the math. In 1991, there were 14 executions in the United States; in 2001, there were 66. According to Ehrlich’s calculation, those 52 additional executions would have accounted for 364 fewer homicides in 2001—not a small drop, to be sure, but less than 4 percent of the actual decrease in homicides that year. So even in a death penalty advocate’s best-case scenario, capital punishment could explain only one twenty-fifth of the drop in homicides in the 1990s. And because the death penalty is rarely given for crimes other than homicide, its deterrent effect cannot account for a speck of decline in other violent crimes.

  It is extremely unlikely, therefore, that the death penalty, as currently practiced in the United States, exerts any real influence on crime rates. Even many of its onetime supporters have come to this conclusion. “I feel morally and intellectually obligated simply to concede that the death penalty experiment has failed,” said U.S. Supreme Court Justice Harry A. Blackmun in 1994, nearly twenty years after he had voted for its reinstatement. “I no longer shall tinker with the machinery of death.”

  So it wasn’t capital punishment that drove crime down, nor was it the booming economy. But higher rates of imprisonment did have a lot to do with it. All those criminals didn’t march into jail by themselves, of course. Someone had to investigate the crime, catch the bad guy, and put together the case that would get him convicted. Which naturally leads to a related pair of crime-drop explanations:

  Innovative policing strategies

  Increased number of police

  Let’s address the second one first. The number of police officers per capita in the United States rose about 14 percent during the 1990s. Does merely increasing the number of police, however, reduce crime? The answer would seem obvious—yes—but proving that answer isn’t so easy. That’s because when crime is rising, people clamor for protection, and invariably more money is found for cops. So if you just look at raw correlations between police and crime, you will find that when there are more police, there tends to be more crime. That doesn’t mean, of course, that the police are causing the crime, just as it doesn’t mean, as some criminologists have argued, that crime will fall if criminals are released from prison.

  To show causality, we need a scenario in which more police are hired for reasons completely unrelated to rising crime. If, for instance, police were randomly sprinkled in some cities and not in others, we could look to see whether crime declines in the cities where the police happen to land.

  As it turns out, that exact scenario is often created by vote-hungry politicians. In the months leading up to Election Day, incumbent mayors routinely try to lock up the law-and-order vote by hiring more police—even when the crime rate is standing still. So by comparing the crime rate in one set of cities that have recently had an election (and which therefore hired extra police) with another set of cities that had no election (and therefore no extra police), it’s possible to tease out the effect of the extra police on crime. The answer: yes indeed, additional police substantially lower the crime rate.

  Again, it may help to look backward and see why crime had risen so much in the first place. From 1960 to 1985, the number of police officers fell more than 50 percent relative to the number of crimes. In some cases, hiring additional police was considered a violation of the era’s liberal aesthetic; in others, it was simply deemed too expensive. This 50 percent decline in police translated into a roughly equal decline in the probability that a given criminal would be caught. Coupled with the above-cited leniency in the other half of the criminal justice system, the courtrooms, this decrease in policing created a strong positive incentive for criminals.

  By the 1990s, philosophies—and necessities—had changed. The policing trend was put in reverse, with wide-scale hiring in cities across the country. Not only did all those police act as a deterrent, but they also provided the manpower to imprison criminals who might have otherwise gone uncaught. The hiring of additional police accounted for roughly 10 percent of the 1990s crime drop.

  But it wasn’t only the number of police that changed in the 1990s; consider the most commonly cited crime-drop explanation of all: innovative policing strategies.

  There was perhaps no more attractive theory than the belief that smart policing stops crime. It offered a set of bona fide heroes rather than simply a dearth of villains. This theory rapidly became an article of faith because it appealed to the factors that, according to John Kenneth Galbraith, most contribute to the formation of conventional wisdom: the ease with which an idea may be understood and the degree to which it affects our personal well-being.

  The story played out most dramatically in New York City, where newly elected mayor Rudolph Giuliani and his handpicked police commissioner, William Bratton, vowed to fix the city’s desperate crime situation. Bratton took a novel approach to policing. He ushered the NYPD into what one senior police official later called “our Athenian period,” in which new ideas were given weight over calcified practices. Instead of coddling his precinct commanders, Bratton demanded accountability. Instead of relying solely on old-fashioned cop know-how, he introduced technological solutions like CompStat, a computerized method of addressing crime hot spots.

  The most compelling new idea that Bratton brought to life stemmed from the broken window theory, which was conceived by the criminologists James Q. Wilson and George Kelling. The broken window theory argues that minor nuisances, if left unchecked, turn into major nuisances: that is, if someone breaks a window and sees it isn’t fixed immediately, he gets the signal that it’s all right to break the rest of the windows and maybe set the building afire too.

  So with murder raging all around, Bill Bratton’s cops began to police the sort of deeds that used to go unpoliced: jumping a subway turnstile, panhandling too aggressively, urinating in the streets, swabbing a filthy squeegee across a car’s windshield unless the driver made an appropriate “donation.”

  Most New Yorkers loved this crackdown on its own merit. But they particularly loved the idea, as stoutly preached by Bratton and Giuliani, that choking off these small crimes was like choking off the criminal element’s oxygen supply. Today’s turnstile jumper might easily be wanted for yesterday’s murder. That junkie peeing in an alley might have been on his way to a robbery.

  As violent crime began to fall dramatically, New Yorkers were more than happy to heap laurels on their operatic, Brooklyn-bred mayor and his hatchet-faced police chief with the big Boston accent. But the two strong-willed men weren’t very good at sharing the glory. Soon after the city’s crime turnaround landed Bratton—and not G
iuliani—on the cover of Time, Bratton was pushed to resign. He had been police commissioner for just twenty-seven months.

  New York City was a clear innovator in police strategies during the 1990s crime drop, and it also enjoyed the greatest decline in crime of any large American city. Homicide rates fell from 30.7 per 100,000 people in 1990 to 8.4 per 100,000 people in 2000, a change of 73.6 percent. But a careful analysis of the facts shows that the innovative policing strategies probably had little effect on this huge decline.

  First, the drop in crime in New York began in 1990. By the end of 1993, the rate of property crime and violent crime, including homicides, had already fallen nearly 20 percent. Rudolph Giuliani, however, did not become mayor—and install Bratton—until early 1994. Crime was well on its way down before either man arrived. And it would continue to fall long after Bratton was bumped from office.

  Second, the new police strategies were accompanied by a much more significant change within the police force: a hiring binge. Between 1991 and 2001, the NYPD grew by 45 percent, more than three times the national average. As argued above, an increase in the number of police, regardless of new strategies, has been proven to reduce crime. By a conservative calculation, this huge expansion of New York’s police force would be expected to reduce crime in New York by 18 percent relative to the national average. If you subtract that 18 percent from New York’s homicide reduction, thereby discounting the effect of the police-hiring surge, New York no longer leads the nation with its 73.6 percent drop; it goes straight to the middle of the pack. Many of those new police were in fact hired by David Dinkins, the mayor whom Giuliani defeated. Dinkins had been desperate to secure the law-and-order vote, having known all along that his opponent would be Giuliani, a former federal prosecutor. (The two men had run against each other four years earlier as well.) So those who wish to credit Giuliani with the crime drop may still do so, for it was his own law-and-order reputation that made Dinkins hire all those police. In the end, of course, the police increase helped everyone—but it helped Giuliani a lot more than Dinkins.

  Most damaging to the claim that New York’s police innovations radically lowered crime is one simple and often overlooked fact: crime went down everywhere during the 1990s, not only in New York. Few other cities tried the kind of strategies that New York did, and certainly none with the same zeal. But even in Los Angeles, a city notorious for bad policing, crime fell at about the same rate as it did in New York once the growth in New York’s police force is accounted for.

  It would be churlish to argue that smart policing isn’t a good thing. Bill Bratton certainly deserves credit for invigorating New York’s police force. But there is frighteningly little evidence that his strategy was the crime panacea that he and the media deemed it. The next step will be to continue measuring the impact of police innovations—in Los Angeles, for instance, where Bratton himself became police chief in late 2002. While he duly instituted some of the innovations that were his hallmark in New York, Bratton announced that his highest priority was a more basic one: finding the money to hire thousands of new police officers.

  Now to explore another pair of common crime-drop explanations:

  Tougher gun laws

  Changes in crack and other drug markets

  First, the guns. Debates on this subject are rarely coolheaded. Gun advocates believe that gun laws are too strict; opponents believe exactly the opposite. How can intelligent people view the world so differently? Because a gun raises a complex set of issues that change according to one factor: whose hand happens to be holding the gun.

  It might be worthwhile to take a step back and ask a rudimentary question: what is a gun? It’s a tool that can be used to kill someone, of course, but more significantly, a gun is a great disrupter of the natural order.

  A gun scrambles the outcome of any dispute. Let’s say that a tough guy and a not-so-tough guy exchange words in a bar, which leads to a fight. It’s pretty obvious to the not-so-tough guy that he’ll be beaten, so why bother fighting? The pecking order remains intact. But if the not-so-tough guy happens to have a gun, he stands a good chance of winning. In this scenario, the introduction of a gun may well lead to more violence.

  Now instead of the tough guy and the not-so-tough guy, picture a high-school girl out for a nighttime stroll when she is suddenly set upon by a mugger. What if only the mugger is armed? What if only the girl is armed? What if both are armed? A gun opponent might argue that the gun has to be kept out of the mugger’s hands in the first place. A gun advocate might argue that the high-school girl needs to have a gun to disrupt what has become the natural order: it’s the bad guys that have the guns. (If the girl scares off the mugger, then the introduction of a gun in this case may lead to less violence.) Any mugger with even a little initiative is bound to be armed, for in a country like the United States, with a thriving black market in guns, anyone can get hold of one.

  There are enough guns in the United States that if you gave one to every adult, you would run out of adults before you ran out of guns. Nearly two-thirds of U.S. homicides involve a gun, a far greater fraction than in other industrialized countries. Our homicide rate is also much higher than in those countries. It would therefore seem likely that our homicide rate is so high in part because guns are so easily available. Research indeed shows this to be true.

  But guns are not the whole story. In Switzerland, every adult male is issued an assault rifle for militia duty and is allowed to keep the gun at home. On a per capita basis, Switzerland has more firearms than just about any other country, and yet it is one of the safest places in the world. In other words, guns do not cause crime. That said, the established U.S. methods of keeping guns away from the people who do cause crime are, at best, feeble. And since a gun—unlike a bag of cocaine or a car or a pair of pants—lasts pretty much forever, even turning off the spigot of new guns still leaves an ocean of available ones.

  So bearing all this in mind, let’s consider a variety of recent gun initiatives to see the impact they may have had on crime in the 1990s.

  The most famous gun-control law is the Brady Act, passed in 1993, which requires a criminal check and a waiting period before a person can purchase a handgun. This solution may have seemed appealing to politicians, but to an economist it doesn’t make much sense. Why? Because regulation of a legal market is bound to fail when a healthy black market exists for the same product. With guns so cheap and so easy to get, the standard criminal has no incentive to fill out a firearms application at his local gun shop and then wait a week. The Brady Act, accordingly, has proven to be practically impotent in lowering crime. (A study of imprisoned felons showed that even before the Brady Act, only about one-fifth of the criminals had bought their guns through a licensed dealer.) Various local gun-control laws have also failed. Washington, D.C., and Chicago both instituted handgun bans well before crime began to fall across the country in the 1990s, and yet those two cities were laggards, not leaders, in the national reduction in crime. One deterrent that has proven moderately effective is a stiff increase in prison time for anyone caught in possession of an illegal gun. But there is plenty of room for improvement. Not that this is likely, but if the death penalty were assessed to anyone carrying an illegal gun, and if the penalty were actually enforced, gun crimes would surely plunge.

  Another staple of 1990s crime fighting—and of the evening news—was the gun buyback. You remember the image: a menacing, glistening heap of firearms surrounded by the mayor, the police chief, the neighborhood activists. It made for a nice photo op, but that’s about as meaningful as a gun buyback gets. The guns that are turned in tend to be heirlooms or junk. The payoff to the gun seller—usually $50 or $100, but in one California buyback, three free hours of psychotherapy—isn’t an adequate incentive for anyone who actually plans to use his gun. And the number of surrendered guns is no match for even the number of new guns simultaneously coming to market. Given the number of handguns in the United States and the number of homicides e
ach year, the likelihood that a particular gun was used to kill someone that year is 1 in 10,000. The typical gun buyback program yields fewer than 1,000 guns—which translates into an expectation of less than one-tenth of one homicide per buyback. Not enough, that is, to make even a sliver of impact on the fall of crime.

  Then there is an opposite argument—that we need more guns on the street, but in the hands of the right people (like the high-school girl above, instead of her mugger). The economist John R. Lott Jr. is the main champion of this idea. His calling card is the book More Guns, Less Crime, in which he argues that violent crime has decreased in areas where law-abiding citizens are allowed to carry concealed weapons. His theory might be surprising, but it is sensible. If a criminal thinks his potential victim may be armed, he may be deterred from committing the crime. Handgun opponents call Lott a pro-gun ideologue, and Lott let himself become a lightning rod for gun controversy. He exacerbated his trouble by creating a pseudonym, “Mary Rosh,” to defend his theory in online debates. Rosh, identifying herself as a former student of Lott’s, praised her teacher’s intellect, his evenhandedness, his charisma. “I have to say that he was the best professor that I ever had,” s/he wrote. “You wouldn’t know that he was a ‘right-wing’ ideologue from the class….There were a group of us students who would try to take any class that he taught. Lott finally had to tell us that it was best for us to try and take classes from other professors more to be exposed to other ways of teaching graduate material.” Then there was the troubling allegation that Lott actually invented some of the survey data that support his more-guns/less-crime theory. Regardless of whether the data were faked, Lott’s admittedly intriguing hypothesis doesn’t seem to be true. When other scholars have tried to replicate his results, they found that right-to-carry laws simply don’t bring down crime.