The number of violent crimes in the United States dropped significantly last year, to what appeared to be the lowest rate in nearly 40 years, a development that was considered puzzling partly because it ran counter to the prevailing expectation that crime would increase during a recession.
The news was not as positive in New York City, however. After leading a long decline in crime rates, the city saw increases in all four types of violent lawbreaking — murder, rape, robbery and aggravated assault — including a nearly 14 percent rise in murders. But data from the past few months suggest the city’s upward trend may have slowed or stopped.
Criminology experts said they were surprised and impressed by the national numbers, issued on Monday by the Federal Bureau of Investigation and based on data from more than 13,000 law-enforcement agencies. They said the decline nationally in the number of violent crimes, by 5.5 percent, raised the question, at least in some places, of to what extent crime could continue to fall — or at least fall at the same pace as the past two years. Violent crimes fell nearly the same amount in 2009.
“Remarkable,” said James Alan Fox, a criminologist at Northeastern University. “Given the fact that we have had some healthy declines in recent years, I fully expected that the improvement would slow. There is only so much air you can squeeze out of a balloon.”