Niles Police Department, IL

On comparing this with another agency

The FBI cautions against ranking jurisdictions against one another, and the caution applies to two of these pages side by side as much as to a list. We publish the rate, the count, the population it divides by and how much of its own record each agency reported, together on the same row, and we say that a figure describes what was reported to police rather than what happened. Nothing here is ranked on a measure the FBI did not publish for it. Its wording is on the ranking page, quoted in full, and at https://ucr.fbi.gov/cautionagainstranking.pdf.

What this data cannot show

• An agency is not a place. This is what the Niles Police Department reported for the population it serves. A city with a transit or university force as well is not the sum of them, and a sheriff’s office covers the part of a county nobody else polices.
• Nothing here is added to a county, state or national total. Two agencies can serve overlapping populations, and summed across a state they reach 101% of its covered population at the median and 128% in Louisiana. The state figures on this site come from the FBI’s own state series, which is a different call.
• Each year’s rate divides by that year’s population, which the FBI publishes beside the counts. Every agency’s population changes annually, by up to 11.4%.
• A year the agency reported nothing is absent rather than shown as zero. The FBI returns 0 for a month nobody submitted and the same 0 for a month in which nothing happened, and nothing in the response separates them.
• Violent and property crime are the FBI’s own aggregations, never sums of component offenses computed here. Offenses are those reported to and recorded by this agency: not convictions, and not what was never reported to police.
• Agencies serving fewer than 25,000 people have no page, because a rate over a few thousand residents moves by a third on one incident.