What Do UCR Numbers Mean?

The 2011 Uniform Crime Report has been issued by the New Jersey State Police, with analyses of crime trends statewide and many other details. For us hyperlocal types, the important stuff is on pages 158 and 159, where statistics for Plainfield in 2011 and 2010 are laid out.

So where to look amongst all those numbers? If you want to say violent crime is down, you can. But you could also say the crime rate per 1,000 of population is up 11 percent. Part of that is due to a whopping 56 percent increase in burglaries.

Arson is up more than 100 percent, the murder rate went up 25 percent, but aggravated assault went down 16 percent. Do these rates look better or worse if you compare 19 cases of arson in 2011 to nine in 2010, 10 murders in 2011 to eight in 2010 or 194 aggravated assaults in 2011 with 231 in 2010?

The point is, statistics can be selected to give a favorable or unfavorable effect.

Two overall markers are the Crime Index and the Crime Rate, as defined below:

CRIME INDEX The total of the seven major offenses used to measure the extent, fluctuation and
distribution of crime in a geographical area. The following crimes make up the index:
Murder, rape, robbery, aggravated assault, burglary, larceny-theft, and motor vehicle
theft; these offenses are referred to as Index offenses.
CRIME RATE The number of Index offenses reported for each unit of population per 1,000.

So in 2011 the Crime Index for Plainfield was 2,155, compared to 1,939 in 2010, an 11 percent increase. The Crime Rate was 43.3 in 2011, compared to 38.9 in 2010, also an 11 percent increase.

It can be hazardous to quote increases when city officials are quoting decreases. In 2009, mayoral candidate Jim Pivnichny was escorted out of the Senior Center by police when he cited a high burglary rate. So be careful out there!

--Bernice