The 1.3 percent drop resumed a long-running decrease. Last year, the FBI said serious crimes leveled off after a steep eight-year decline, leading some criminal justice experts to wonder whether U.S. crime rates may be heading higher.
The FBI said the number of murders in the first six months went up by 0.3 percent while the total for robberies increased by 0.8 percent.
But other offenses that make up the violent crimes category decreased, with rapes down by 1.7 percent and aggravated assaults falling by 2.4 percent, the FBI said.
Lower crime rates generally have been attributed to various factors, including improved police tactics, demographic changes, the record U.S. prison population and the demise of the crack cocaine markets that helped send crime rates soaring in the late 1980s, criminal justice experts have said.
They have been watching closely whether the crime numbers keep declining or starting increasing.
The FBI said so-called property crimes, which include burglary, larceny, theft and motor vehicle theft, decreased by 0.2 percent from January through June from the year-ago level.
Not every region had fewer crimes in the first six months of this year.
Crime fell 4 percent in the Northeast and nearly 2 percent in the Midwest but rose 1.6 percent in the West and 0.8 percent in the South.
Crime levels went down in the biggest cities, with a population of more than 1 million, and in suburban and rural counties, the FBI said. Increases occurred in cities with a population ranging from 100,000 to 1 million.
The FBI crime report is based on data reported voluntarily from 17,000 local and state law enforcement agencies representing 94 percent of the U.S. population.
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