The Better Angels of Our Nature: Why Violence Has Declined

by Steven Pinker

  RECIVILIZATION IN THE 1990s

  It would be a mistake to think of the 1960s crime boom as undoing the decline of violence in the West, or as a sign that historical trends in violence are cyclical, yo-yoing up and down from one era to the next. The annual homicide rate in the United States at its recent worst—10.2 per 100,000 in 1980—was a quarter of the rate for Western Europe in 1450, a tenth of the rate of the traditional Inuit, and a fiftieth of the average rate in nonstate societies (see figure 3–4).

  And even that number turned out to be a high-water mark, not a regular occurrence or a sign of things to come. In 1992 a strange thing happened. The homicide rate went down by almost 10 percent from the year before, and it continued to sink for another seven years, hitting 5.7 in 1999, the lowest it had been since 1966.131 Even more shockingly, the rate stayed put for another seven years and then drooped even further, from 5.7 in 2006 to 4.8 in 2010. The upper line in figure 3–18 plots the American homicide trend since 1950, including the new lowland we have reached in the 21st century.

  The graph also shows the trend for Canada since 1961. Canadians kill at less than a third of the rate of Americans, partly because in the 19th century the Mounties got to the western frontier before the settlers and spared them from having to cultivate a violent code of honor. Despite this difference, the ups and downs of the Canadian homicide rate parallel those of their neighbor to the south (with a correlation coefficient between 1961 and 2009 of 0.85), and it sank almost as much in the 1990s: 35 percent, compared to the American decline of 42 percent.132

  The parallel trajectory of Canada and the United States is one of many surprises in the great crime decline of the 1990s. The two countries differed in their economic trends and in their policies of criminal justice, yet they enjoyed similar drops in violence. So did most of the countries of Western Europe.133 Figure 3–19 plots the homicide rates of five major European countries over the past century, showing the historical trajectory we have been tracking: a long-term decline that lasted until the 1960s, an uptick that began in that tumultuous decade, and the recent return to more peaceable rates. Every major Western European country showed a decline, and though it looked for a while as if England and Ireland would be the exceptions, in the 2000s their rates dropped as well.

  FIGURE 3–18. Homicide rates in the United States, 1950–2010, and Canada, 1961–2009

  Sources: Data for United States are from the FBI Uniform Crime Reports 1950–2010: U.S. Bureau of Justice Statistics, 2009; U.S. Federal Bureau of Investigation, 2010b, 2011; Fox & Zawitz, 2007. Data for Canada, 1961–2007: Statistics Canada, 2008. Data for Canada, 2008: Statistics Canada, 2010. Data for Canada, 2009: K. Harris, “Canada’s crime rate falls,” Toronto Sun, Jul. 20, 2010.

  Not only did people cut down on killing, but they refrained from inflicting other kinds of harm. In the United States the rates of every category of major crime dropped by about half, including rape, robbery, aggravated assault, burglary, larceny, and even auto theft.134 The effects were visible not just in the statistics but in the fabric of everyday life. Tourists and young urban professionals recolonized American downtowns, and crime receded as a major issue from presidential campaigns.

  None of the experts had predicted it. Even as the decline was under way, the standard opinion was that the rise in crime that had begun in the 1960s would even get worse. In a 1995 essay James Q. Wilson wrote:Just beyond the horizon, there lurks a cloud that the winds will soon bring over us. The population will start getting younger again. By the end of this decade there will be a million more people between the ages of fourteen and seventeen than there are now. This extra million will be half male. Six percent of them will become high-rate, repeat offenders—30,000 more young muggers, killers, and thieves than we have now. Get ready.135

  FIGURE 3–19. Homicide rates in five Western European countries, 1900–2009

  Sources: Data from Eisner, 2008, except England, 2009, which is from Walker et al., 2009; population estimate from U.K. Office for National Statistics, 2009.

  The cloud beyond the horizon was joined by purple prose from other talking heads on crime. James Alan Fox predicted a “blood bath” by 2005, a crime wave that would “get so bad that it [would] make 1995 look like the good old days.”136 John DiIulio warned of more than a quarter of a million new “super-predators on the streets” by 2010 who would make “the Bloods and the Crips look tame by comparison.”137 In 1991 the former editor of the Times of London predicted that “by the year 2000, New York could be a Gotham City without Batman.”138

  As legendary New York mayor Fiorello La Guardia might have said, “When I make a mistake, it’s a beaut!” (Wilson was a good sport about it, remarking, “Social scientists should never try to predict the future; they have enough trouble predicting the past.”) The mistake of the murder mavens was to have put too much faith in the most recent demographic trends. The crack-fueled violence bubble of the late 1980s involved large numbers of teenagers, and the population of teenagers was set to grow in the 1990s as an echo of the baby boom. But the overall crime-prone cohort, which includes twenty-somethings as well as teenagers, actually fell in the 1990s.139 Even this corrected statistic, though, cannot explain the decline of crime in that decade. The age distribution of a population changes slowly, as each demographic pig makes its way through the population python. But in the 1990s the crime rate lurched downward for seven straight years and promptly parked itself at its new bottom for another nine. As with the takeoff of crime in the 1960s, changes in the rate of violence for each age cohort swamped the effect of the size of those cohorts.

  The other usual suspect in explaining crime trends, the economy, did little better in explaining this one. Though unemployment went down in the United States in the 1990s, it went up in Canada, yet violent crime decreased in Canada as well.140 France and Germany also saw unemployment go up while violence went down, whereas Ireland and the U.K. saw unemployment go down while violence went up.141 This is not as surprising as it first appears, since criminologists have long known that unemployment rates don’t correlate well with rates of violent crime.142 (They do correlate somewhat with rates of property crime.) Indeed, in the three years after the financial meltdown of 2008, which caused the worst economic downturn since the Great Depression, the American homicide rate fell by another 14 percent, leading the criminologist David Kennedy to explain to a reporter, “The idea that everyone has ingrained into them—that as the economy goes south, crime has to get worse—is wrong. It was never right to begin with.”143

  Among economic measures, inequality is generally a better predictor of violence than unemployment.144 But the Gini coefficient, the standard index of income inequality, actually rose in the United States from 1990 to 2000, while crime was falling, and it had hit its low point in 1968, when crime was soaring.145 The problem with invoking inequality to explain changes in violence is that while it correlates with violence across states and countries, it does not correlate with violence over time within a state or country, possibly because the real cause of the differences is not inequality per se but stable features of a state’s governance or culture that affect both inequality and violence.146 (For example, in unequal societies, poor neighborhoods are left without police protection and can become zones of violent anarchy.)

  Yet another false lead may be found in the kind of punditry that tries to link social trends to the “national mood” following current events. The terrorist attacks of September 11, 2001, led to enormous political, economic, and emotional turmoil, but the homicide rate did not budge in response.

  The 1990s crime decline inspired one of the stranger hypotheses in the study of violence. When I told people I was writing a book on the historical decline of violence, I was repeatedly informed that the phenomenon had already been solved. Rates of violence have come down, they explained to me, because after abortion was legalized by the 1973 Roe v. Wade U.S. Supreme Court decision, the unwanted children who would ordinarily have grown up to be crimina
ls were not born in the first place, because their begrudging or unfit mothers had had abortions instead. I first heard of this theory in 2001 when it was proposed by the economists John Donohue and Steven Levitt, but it seemed too cute to be true.147 Any hypothesis that comes out of left field to explain a massive social trend with a single overlooked event will almost certainly turn out to be wrong, even if it has some data supporting it at the time. But Levitt, together with the journalist Stephen Dubner, popularized the theory in their bestseller Freakonomics , and now a large proportion of the public believes that crime went down in the 1990s because women aborted their crime-fated fetuses in the 1970s.

  To be fair, Levitt went on to argue that Roe v. Wade was just one of four causes of the crime decline, and he has presented sophisticated correlational statistics in support of the connection. For example, he showed that the handful of states that legalized abortion before 1973 were the first to see their crime rates go down.148 But these statistics compare the two ends of a long, hypothetical, and tenuous causal chain—the availability of legal abortion as the first link and the decline in crime two decades later as the last—and ignore all the links in between. The links include the assumptions that legal abortion causes fewer unwanted children, that unwanted children are more likely to become criminals, and that the first abortion-culled generation was the one spearheading the 1990s crime decline. But there are other explanations for the overall correlation (for example, that the large liberal states that first legalized abortion were also the first states to see the rise and fall of the crack epidemic), and the intermediate links have turned out to be fragile or nonexistent.149

  To begin with, the freakonomics theory assumes that women were just as likely to have conceived unwanted children before and after 1973, and that the only difference was whether the children were born. But once abortion was legalized, couples may have treated it as a backup method of birth control and may have engaged in more unprotected sex. If the women conceived more unwanted children in the first place, the option of aborting more of them could leave the proportion of unwanted children the same. In fact, the proportion of unwanted children could even have increased if women were emboldened by the abortion option to have more unprotected sex in the heat of the moment, but then procrastinated or had second thoughts once they were pregnant. That may help explain why in the years since 1973 the proportion of children born to women in the most vulnerable categories—poor, single, teenage, and African American—did not decrease, as the freakonomics theory would predict. It increased, and by a lot.150

  What about differences among individual women within a crime-prone population? Here the freakonomics theory would seem to get things backwards. Among women who are accidentally pregnant and unprepared to raise a child, the ones who terminate their pregnancies are likely to be forward-thinking, realistic, and disciplined, whereas the ones who carry the child to term are more likely to be fatalistic, disorganized, or immaturely focused on the thought of a cute baby rather than an unruly adolescent. Several studies have borne this out.151 Young pregnant women who opt for abortions get better grades, are less likely to be on welfare, and are more likely to finish school than their counterparts who have miscarriages or carry their pregnancies to term. The availability of abortion thus may have led to a generation that is more prone to crime because it weeded out just the children who, whether through genes or environment, were most likely to exercise maturity and self-control.

  Also, the freakonomists’ theory about the psychological causes of crime comes right out of “Gee, Officer Krupke,” when a gang member says of his parents, “They didn’t wanna have me, but somehow I was had. Leapin’ lizards! That’s why I’m so bad!” And it is about as plausible. Though unwanted children may grow up to commit more crimes, it is more likely that women in crime-prone environments have more unwanted children than that unwantedness causes criminal behavior directly. In studies that pit the effects of parenting against the effects of the children’s peer environment, holding genes constant, the peer environment almost always wins.152

  Finally, if easy abortion after 1973 sculpted a more crime-averse generation, the crime decline should have begun with the youngest group and then crept up the age brackets as they got older. The sixteen-year-olds of 1993, for example (who were born in 1977, when abortions were in full swing), should have committed fewer crimes than the sixteen-year-olds of 1983 (who were born in 1967, when abortion was illegal). By similar logic, the twenty-two-year-olds of 1993 should have remained violent, because they were born in pre-Roe 1971. Only in the late 1990s, when the first post-Roe generation reached their twenties, should the twenty-something age bracket have become less violent. In fact, the opposite happened. When the first post-Roe generation came of age in the late 1980s and early 1990s, they did not tug the homicide statistics downward; they indulged in an unprecedented spree of mayhem. The crime decline began when the older cohorts, born well before Roe, laid down their guns and knives, and from them the lower homicide rates trickled down the age scale.153

  So how can we explain the recent crime decline? Many social scientists have tried, and the best that they can come up with is that the decline had multiple causes, and no one can be certain what they were, because too many things happened at once.154 Nonetheless, I think two overarching explanations are plausible. The first is that the Leviathan got bigger, smarter, and more effective. The second is that the Civilizing Process, which the counterculture had tried to reverse in the 1960s, was restored to its forward direction. Indeed, it seems to have entered a new phase.

  By the early 1990s, Americans had gotten sick of the muggers, vandals, and drive-by shootings, and the country beefed up the criminal justice system in several ways. The most effective was also the crudest: putting more men behind bars for longer stretches of time. The rate of imprisonment in the United States was pretty much flat from the 1920s to the early 1960s, and it even declined a bit until the early 1970s. But then it shot up almost fivefold, and today more than two million Americans are in jail, the highest incarceration rate on the planet.155 That works out to three-quarters of a percent of the entire population, and a much larger percentage of young men, especially African Americans.156 The American imprisonment binge was set off in the 1980s by several developments. Among them were mandatory sentencing laws (such as California’s “Three Strikes and You’re Out”), a prison-building boom (in which rural communities that had formerly shouted “Not in my backyard!” now welcomed the economic stimulus), and the War on Drugs (which criminalized possession of small amounts of cocaine and other controlled substances).

  Unlike the more gimmicky theories of the crime decline, massive imprisonment is almost certain to lower crime rates because the mechanism by which it operates has so few moving parts. Imprisonment physically removes the most crime-prone individuals from the streets, incapacitating them and subtracting the crimes they would have committed from the statistics. Incarceration is especially effective when a small number of individuals commit a large number of crimes. A classic study of criminal records in Philadelphia, for example, found that 6 percent of the young male population committed more than half the offenses.157 The people who commit the most crimes expose themselves to the most opportunities to get caught, and so they are the ones most likely to be skimmed off and sent to jail. Moreover, people who commit violent crimes get into trouble in other ways, because they tend to favor instant gratification over long-term benefits. They are more likely to drop out of school, quit work, get into accidents, provoke fights, engage in petty theft and vandalism, and abuse alcohol and drugs.158 A regime that trawls for drug users or other petty delinquents will net a certain number of violent people as bycatch, further thinning the ranks of the violent people who remain on the streets.

  Incarceration can also reduce violence by the familiar but less direct route of deterrence. An ex-convict might think twice about committing another crime once he gets out of jail, and the people who know about him might think twice about
following in his footsteps. But proving that incarceration deters people (as opposed to incapacitating them) is easier said than done, because the statistics at any time are inherently stacked against it. The regions with the highest rates of crime will throw the most people in jail, creating the illusion that imprisonment increases crime rather than decreasing it. But with suitable ingenuity (for example, correlating increases in imprisonment at one time with decreases in crime at a later time, or seeing if a court order to reduce the prison population leads to a subsequent increase in crime), the deterrence effect can be tested. Analyses by Levitt and other statisticians of crime suggest that deterrence works.159 Those who prefer real-world experiments to sophisticated statistics may take note of the Montreal police strike of 1969. Within hours of the gendarmes abandoning their posts, that famously safe city was hit with six bank robberies, twelve arsons, a hundred lootings, and two homicides before the Mounties were called in to restore order.160

  But the case that the incarceration boom led to the crime decline is far from watertight.161 For one thing, the prison bulge began in the 1980s, but violence did not decline until a decade later. For another, Canada did not go on an imprisonment binge, but its violence rate went down too. These facts don’t disprove the theory that imprisonment mattered, but they force it to make additional assumptions, such as that the effect of imprisonment builds up over time, reaches a critical mass, and spills over national borders.