Rising rates of crime draw the attention of politicians, journalists, and social scientists, but the same does not seem to be true of falling rates of crime. A more than decade-long drop in crime in the United States that began in the 1990s has received very little attention from these quarters. Zimring gently chastises his profession for its preoccupation with the negative, suggesting that falling crime rates have many beneficial effects on peoples' lives, and also have the potential to soften harsh public policies. Zimring's goal, however, is to understand the crime decline, not to assess its impact. He systematically unpacks the good news about crime with the tools of his trade as a criminologist.
Zimring begins by describing the (declining) crime scene, and then moves to “the usual suspects” (imprisonment, economy, demography) to begin to explain it. The rising incarceration rate, improved economic performance, and shrinking proportion of young people in the population have helped reduce crime rates, he concludes, but they are only a partial explanation. Inspector Zimring then moves on to three additional factors that have drawn the attention of criminologists and economists seeking to explain crime trends: changes in the size and activities of police forces, the passing of the epidemic of crack cocaine, and increased access to abortion.
This discussion of explanatory factors suggests rivalry between criminologists and economists, who tend to stick with their rational-choice-based paradigm. Zimring's demonstration of its weaknesses is compelling. The availability of legal abortion, for example, has not actually translated into declining birth rates in the most vulnerable groups.
At this point Zimring turns to Canada, which has experienced a very similar drop in crime, but without increasing its incarceration rate or the size of its police force, suggesting that these factors do not have the effects that have been claimed for them. What Canada and the United States do have in common is declining birth rates in the 1970s and 1980s, producing a shrinking base of young adults in the 1990s in their crime-prone years. Zimring resists putting too much weight on these changes, however, because they do not always have the expected impact on crime rates.
This forces a finesse. The “prudent view” is that “cyclical variations without any further current explanation play a major role in the Canadian decline, and for that reason can also be expected to be an important part of the U. S. story as well” (p. 131). He never explains, however, what such cycles entail.
But Zimring rallies with a chapter on New York City, the poster city for crime reduction in the 1990s. In New York, all crime indexes dropped at about twice the rate of any other city over the decade, by about 63 percent overall. This occurred, Zimring asserts, without any significant changes in the city except in the size and deployment of the metropolitan police forces. The “excess” reduction in crime that New York experienced in the 1990s, he suggests, is attributable to a 35 percent increase in the police force and administrative changes introduced by Police Chief William Bratton after his appointment in 1994. Without explaining how these changes could have been so effective, Zimring essentially credits them with half of the city's crime decline in the 1990s.
This book can be recommended to all audiences as a readable tour de force in unpacking aggregate statistics about crime in the context of changes in demographic, economic, and crime-policy trends. Zimring, a leader in his field, is a cheerful and irreverent guide through the available research. He is generous in his acknowledgments, straightforward in his critique, imaginative in his use of aggregate data, and generally modest in claiming insights from data. He argues persuasively for studying widely divergent cases and for comparative analysis. He is circumspect in claiming trends before they are firmly established. Zimring is vulnerable, however, in some of the assumptions he makes about law and society. He claims that these changes occurred “without any fundamental change in the population composition, economy, or ecology” of the New York City area. But is this true? According to the New York City Department of City Planning,
The passage of the 1965 Immigration and Nationality Amendments led to a surge in immigration to New York City and a decline in the share of European immigrants. Between 1970 and 2000, the total foreign-born population nearly doubled, from 1.44 million to 2.87 million, while the share of Europeans dropped, from 64 percent to 19 percent. Latin America was the largest area of origin in 2000, accounting for nearly 32 percent of the city's foreign-born, followed by Asia (24 percent), the non-Hispanic Caribbean (21 percent), Europe (19 percent), and Africa (3 percent). Thus New York City's foreign-born in 2000 had extremely diverse origins, in contrast to the overwhelming European origin of the foreign-born in earlier decades.
(New York City Department of City Planning 2008: n.p.)Such facts raise a broader question. What variables should be included in a model to explain crime trends?
Zimring argues persuasively against atheoretical regression models that conflate correlation with causation. But we are left with the mysterious crime cycles to explain much of the crime drop, and a police-based explanation to explain the rest. Perhaps inadvertently, Zimring has demonstrated the need for a broader-based explanation of crime trends.
