A recent FBI report found that the national crime rate has continued to drop:
The 2011 report represents a 30.6 drop in property crime since 1991, and a 38 percent drop in violent crime since 1992. Gary LaFree, a criminology professor at the University of Maryland, told MSNBC.com that a combination of factors have contributed to the decline. "There is some truth to the fact that younger people commit more crimes,” he said. “We also have a record number of immigrants, and contrary to popular belief, immigrants have lower crime rates than the rest of society.”
Franklin Zimring explains how NYC successfully fought crime:
First of all, cops matter. For at least a generation, the conventional wisdom in American criminal justice doubted the ability of urban police to make a significant or sustained dent in urban crime. The details on cost-effectiveness and best tactics have yet to be established, but investments in policing apparently carry at least as much promise as investments in other branches of crime control in the U.S.
Two other important lessons are that reducing crime does not require reducing the use of drugs or sending massive numbers of people to jail. Incidentally, the difference between New York’s incarceration trends and those of the rest of the nation—and the money that the city and state governments avoided pouring into the correctional business—has more than paid for the city’s expanded police force.