FBI Cautions Against Ranking, Drawing Conclusions By Making Direct Comparisons of Crime Reporting Statistics Between Cities

The Village of Arlington Heights recently proclaimed that Arlington Heights ranked favorably in studies of crime statistics because it ranked as the 3rd safest city in the United States. However, careful analysis of the claim raises skepticism to the importance and relevance of the claim because …

#1) the FBI cautions against using such comparisons of their data (Uniform Crime Reporting statistics or UCR),

#2) the FBI has a longstanding policy against ranking participating law enforcement agencies on the basis of crime data alone, and

#3) a study by at least one of the websites (Reviews.com) excluded seven of our nearest neighboring communities because of a population criteria that excluded communities with populations less than 50,000.

Consumer research website Reviews.com claims it’s good to get a sense of how your city compares to others in the country in terms of safety. To help readers better understand this information, Reviews.com claims they analyzed the FBI’s most recent crime report and looked at 454 cities to find which are the safest. Reviews.com then listed the top 100 safest cities in the United States. The Village of Arlington Heights relayed the Reviews.com information and results from another website NeighborhoodScout.com by posting an article “Village’s Historic Low Crime Rate Acknowledged” on the official village website on April 22, 2019. The article included a quote from Arlington Heights Police Chief Gerald Mourning.

“Being named to these lists is confirmation of the professional police work that we do in Arlington Heights which reflects favorably on our community’s profile.”

— Police Chief Gerald Mourning

There is no doubt that Mourning’s statement is true regarding the favorable quality of police work in Arlington Heights, but the emphasis by the village on ranking Arlington Heights as the 3rd safest city in the United States goes against the advice of the FBI. “Comparisons [of communities] lead to simplistic and/or incomplete analyses that often create misleading perceptions adversely affecting communities and their residents,” according to the FBI.

Additionally, while Reviews.com implied that young parents and retirees could use this ranking to help plan moves from one city to another, the FBI cautions that “valid assessments are possible only with careful study and analysis of the range of unique conditions affecting each local law enforcement jurisdiction.”

For both young parents putting down roots and retirees preparing for the next chapter, it’s helpful to know which cities are relatively low-crime when planning a move.

— Reviews.com

Reviews.com lists a “Total Crimes Score” which Arlington Heights ranked third with a figure of 1.349. Reviews.com explained that in calculating the score, they weighed violent crime higher than property crimes in the scoring. In defining safest cities, Reviews.com admits they excluded communities with populations under 50,000. For example, Cardinal News noticed that our neighbors in Rolling Meadows were not on the list of safest cities because the population of Rolling Meadows is only about 24,099. Neither were the following communities: Buffalo Grove (pop. 41,496), Elk Grove Village (pop. 33,127), Inverness (pop. 7,399), Long Grove (pop. 8,043), Prospect Heights (pop. 16,256), and Wheeling (pop. 37,648) also were not on the list because their population figures were below 50,000. The filtering out of six municipalities in the “Safest List” reduces the already misleading list by diluting the relevance of comparing nearby communities in the northwest suburbs.

Population Density and Degree of Urbanization Affects Crime Statistics

Also, keep in mind that as the population density of Arlington Heights increases, the crime rate could go down in the following manner. Imagine a block in Arlington Heights that has remained undeveloped for years with only four houses on the block. Suppose the block in Arlington Heights is developed to add a large 13-story high-rise with 150 apartment units with an average of 1.5 people per unit or 225 total people in the new apartment building towering over the four houses on the block. Suppose those four houses have a total of 12 family members in the four houses (2 people each in two houses, 3 in one house and five in another). Now the total population on the block is 237 people. Suppose there was one violent assault on the block during the latest year when only 12 people lived on the block — producing a crime rate of .0833 per person (1/12). Suppose the next year, after the new apartment building is built and opened, there are 10 violent assaults on the block. There are 9 additional assaults on the block, but the crime rate equals 0.042 per person (10/237), and shows the crime rate for the block is cut in half. The workload for the police department increases tenfold, but the crime rate reported to the public drops in half. Misleading.

In the final sentence of the Reviews.com report, the website provided a disclaimer saying, “Remember that these are just estimated predictions, however, and a variety of factors play a part in any city’s safety.”

Here is the full caution from the FBI regarding the Uniform Crime Report, January – June 2018 …

“Figures used in this Report were submitted voluntarily by law enforcement agencies throughout the country. Individuals using these tabulations are cautioned against drawing conclusions by making direct comparisons between cities. Comparisons lead to simplistic and/or incomplete analyses that often create misleading perceptions adversely affecting communities and their residents. Valid assessments are possible only with careful study and analysis of the range of unique conditions affecting each local law enforcement jurisdiction. It is important to remember that crime is a social problem and, therefore, a concern of the entire community. In addition, the efforts of law enforcement are limited to factors within its control. The data user is, therefore, cautioned against comparing statistical data of individual agencies. Further information on this topic can be obtained in Uniform Crime Reporting Statistics: Their Proper Use.”

— FBI Crime Report January – June 2018

Proper Use

UCR data are sometimes used to compile rankings of individual jurisdictions and institutions of higher learning. These incomplete analyses have often created misleading perceptions which adversely affect geographic entities and their residents. For this reason, the FBI has a longstanding policy against ranking participating law enforcement agencies on the basis of crime data alone. Despite repeated warnings against these practices, some data users continue to challenge and misunderstand this position.

Data users should not rank locales because there are many factors that cause the nature and type of crime to vary from place to place. UCR statistics include only jurisdictional population
figures along with reported crime, clearance, or arrest data. Rankings ignore the uniqueness of each locale.

According to the FBI, some factors that are known to affect the volume and type of crime occurring from place to place are:

• Population density and degree of urbanization.

• Variations in composition of the population, particularly youth concentration.

• Stability of the population with respect to residents; mobility, commuting patterns, and transient factors.

• Economic conditions, including median income, poverty level, and job availability.

• Modes of transportation and highway systems.

• Cultural factors and educational, recreational, and religious characteristics.

• Family conditions with respect to divorce and family cohesiveness.

• Climate.

• Effective strength of law enforcement agencies.

• Administrative and investigative emphases on law enforcement.

• Policies of other components of the criminal justice system (i.e., prosecutorial, judicial, correctional, and probational).

• Citizens’ attitudes toward crime.

• Crime reporting practices of the citizenry.

Most educated people understand that statistics can be used to inform or mislead. There’s even a humorous book written about the topic by Darrell Huff, How to Lie with Statistics (available on Amazon). The concern in this case with Arlington Heights: Was this just carelessness use of statistics, or deliberate misleading of the public with a cognizant disregard for the FBI caution?


CARDINAL NEWS | Arlington 425 at Campbell St and Highland Ave in Arlington Heights Is on a Fast Track, But Some People Say Not So Fast

See also …

FBI | Uniform Crime Reporting Statistics: Their Proper Use [PDF]



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