Figures released Monday by the FBI show national declines in murder, car thefts and other crimes. The ebbing crime rates make this recession different from other economic downturns in the past half-century.

High unemployment. More people on food stamps. Fewer homeowners. Yet for all the signs of recession, one thing is missing: more crime.


Nationally, at least.


Figures released Monday by the FBI show national declines in murder, car thefts and other crimes. The trend was not as pronounced in Massachusetts, where certain crimes in select cities were on the rise.


But experts are scratching their heads over ebbing crime rates, which make this recession different from other economic downturns in the past half-century. Among the early guesses as to the reasons: jobless people being at home, where they can watch for thieves, and the American population getting older. Older people generally commit fewer crimes.


The FBI figures, preliminary tabulations from the first half of 2009, show crime falling across the country, even at a time of high unemployment, foreclosures and layoffs. Most surprisingly, murder and manslaughter were down 10 percent.


Property crimes, in particular, were expected to rise, but they haven’t.


Overall, property crimes fell by 6.1 percent, and violent crimes by 4.4 percent, according to the data. Crime rates haven’t been this low since the 1960s, and are nowhere near the peak reached in the early 1990s.


Violent crime in the six-month period rose in every Massachusetts city with a population of more than 100,000, except for Boston. (The others are Cambridge, Lowell, Springfield and Worcester.)


In Norfolk County, nine people have been murdered in 2009 compared with five in 2006, seven in 2007, and six last year.


In Boston, the FBI figures show slight declines in murders, robberies, aggravated assaults, burglaries and car thefts. Property crimes remained steady and forcible rapes jumped from 110 to 131.


Nationwide, rape fell by 3.3 percent, robbery by 6.5 percent. Car theft fell by nearly 19 percent, continuing a sharp downward trend. Some believe that big drop in car theft is due largely to the security locking systems installed on most models, as well as more high-tech deterrents such as car recovery devices that use the Global Positioning System.


Talking about possible explanations for falling crime, University of Missouri-St. Louis sociologist Richard Rosenfeld said extended unemployment benefits, food stamps, and other government-driven economic stimulus “have cushioned and delayed for many people the big blows that come from a recession.”


James Alan Fox, a criminal justice professor at Northeastern University, said he was not surprised by the overall downward trends.


“The popular wisdom is wrong,” Fox said. “If a law-abiding citizen loses their job, they don’t typically go on a crime spree.”


Fox thinks the decline is partly due to the graying of America. As the over-50 population grows, crime goes down, even while social costs like health care go up, he said.


The figures are based on data supplied to the FBI by more than 11,700 police and law enforcement agencies. They compare reported crimes in the first six months of this year to the first six months of last year. Separate statistics compiled by the Justice Department measure both reported and unreported crimes.


The Patriot Ledger