Violent crime data in Essex County, as reported by the FBI Uniform Crime Report.
ESSEX COUNTY -- Crime rates in the municipalities across the county vary greatly. According to violent crime rates calculated from the recently released 2014 FBI "Crime in the United States" report, towns in Essex range from North Caldwell - which reported 0 violent crimes all year - to Irvington, which had a rate of 12.6 violent crimes per every 1,000 residents.
But, experts say, those crime rates and comparisons need to be taken with a grain of salt.
"It's a good way to arrive at a common denominator," Wayne Fisher, a criminal justice professor and director of the Police Institute at Rutgers, said in a phone interview Friday.
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"It's helpful, but it doesn't measure everything that goes into developing perceptions of safety."
For example, Fisher said, looking just at violent crime data, does not take into account other factors "that we know to be associated with crime," like transient population, daytime population (the number of people who travel into or out of a given municipality each day), socio-economic conditions, population and housing density, and the number of major highways that are located in each town.
Overall, the FBI report indicated that violent crime in New Jersey decreased in 2014. Violent crime statewide reported a rate of 261 offenses per 100,000 residents, lower than the rates in New York and Pennsylvania, as well as the nation as a whole.
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In a statement released with the data, FBI Director Jim Comey said the reported rates are only a piece of the puzzle when formulating crime-fighting initiatives.
"While tallying the numbers of homicides, armed robberies, aggravated assaults, and other crimes is useful, it does not go far enough to help us determine how these crimes occur and what we can do to prevent these crimes in the first place," he said in the statement.
Jessica Mazzola may be reached at jmazzola@njadvancemedia.com. Follow her on Twitter @JessMazzola. Find NJ.com on Facebook.