Category: Policing

The potential of the UCR

What is the UCR?

There are over 18,000 independent police agencies in the U.S. Annually, the U.S. spends $120 billion on police protection, with over two-thirds of those expenditures coming from local revenue sources. On average, police protection costs about $275 per person annually1.

The Uniform Crime Reporting (UCR) Program provides uniform, consistent data on the activity of police departments and their use of funds. It is administered by the Federal Bureau of Investigation (FBI). The UCR collects summary statistics on crimes known to the police, arrests, and law enforcement officers killed and assaulted. It has a uniform definition of crimes and police activities to allow for comparison over time and across jurisdictions.

The program was created by the International Association of Chiefs of Police in 1929 as a voluntary data collection to produce reliable and uniform crime statistics (the FBI took over the program the following year). Today, the FBI uses the data collected by the UCR to produce summary publications describing the state of crime in the U.S. Though the collection is voluntary, over 18,000 city, university/college, state, tribal, and federal law enforcement agencies participate.

What can the UCR tell us?

The UCR provides information on police, criminal activity, and public safety. This includes:

  • The size and composition of police forces
  • The prevalence of crimes reported to the police and rates at which police departments “clear” them
  • The race, age, and gender of all arrestees by the type of offense committed
  • The value of property stolen or damaged and the amount that police were able to recover

Here are just some of the questions that can be answered using the UCR data:

  1. How many police officers are there in my town?
  2. How many more arrests did the police make for drug offenses than for assaults?
  3. How many more non-white people were arrested for drug offenses than white people?
  4. How many burglaries occurred per 1,000 people in my town last year? How does this compare to nearby towns, to my state, and to the nation?
  5. What percentage of vandalism reported to police did the police later clear?

Another advantage of UCR data is that they can become even more useful when combined with other publicly available data, such as US Census Bureau data. Adding information about the demographics of a community and its economic conditions provides the context needed to ask further questions, including:

  1. Is there a racial bias in arrest rates for different crimes in my town?
  2. How does the arrest rate for non-violent offenses in my town compare to towns across the country that have similar socioeconomic conditions?
  3. How has police emphasis on enforcing marijuana possession laws changed over time?

Why not just use data from cities themselves?

Three reasons:

  1. Cities have more control over definitions, collection procedures, and reporting of data for collections that do not have a uniform standard. This makes comparisons between cities difficult if not impossible to do in an authoritative way. In contrast, the UCR attempts to provide a standard, uniform method of categorizing crimes and arrests, making comparisons across jurisdictions possible.
  2. Only some cities possess the resources to develop, maintain, and curate their own additional data collection beyond the UCR. Outside of the largest 100 or so police departments, the UCR is the only data collection that is consistently available to members of the public.
  3. Cities are already participating in and using the UCR and it represents an existing investment in data collection. Use of this collection will increase its relevance.

The power in the UCR comes not from the depth of the data it collects, but from the breadth. Only the UCR allows us to draw meaningful comparisons over time and across jurisdictions.

Where to find UCR data

The canonical source of agency-level UCR data is the National Archive of Criminal Justice Data (NACJD). The NACJD collects, curates, updates, and maintains archival data collections for many crime and justice programs, including the UCR. The NCJD is sponsored by the Bureau of Justice Statistics, the National Institute of Justice, and the Office of Juvenile Justice and Delinquency Prevention at the United States Department of Justice.

The NACJD is part of the Inter-University Consortium for Political and Social Research (ICPSR), a research center at the Institute for Social Research (ISR) located at the University of Michigan.

Limitations of UCR

The UCR is not a good way to measure crime because most criminal activity is underreported to police and underreporting varies by community, type of crime, and victim (Karmen 2010). We know this because of data collections like the National Crime Victim Survey (NCVS), which is an attempt to understand the victims’ perspective on crime. The UCR has other drawbacks addressed by the NCVS which include incorporating types of crimes that do not fit well in the nearly 60 year old UCR such as stalking, intimidation, identity theft, and other online fraud.

The UCR is also being replaced — or upgraded in a sense — by a collection known as the National Incident Based Reporting System (NIBRS). Though it still focuses on crimes reported to police, NIBRS is an attempt to get much more detailed information about each incident reported to police including information on the perpetrator, the victim, and others connected with the crime. NIBRS is still in the process of being adopted — in 2017 approximately 43% of UCR participating law enforcement agencies participated and the FBI expects to fully replace the original UCR collection with NIBRS data on January 1, 2021.2

Even with these limitations though the UCR remains the most comprehensive and longest-running data collection on many aspects of policing including staffing levels and arrest behaviors.3

Tools for exploring UCR data

There are a number of online tools that allow you to explore agency-level data from the UCR. Two that I recommend are:

Karmen, Andrew. 2010. Crime Victims: An Introduction to Victimology. 7th ed. Australia ; Belmont, CA: Wadsworth Cengage Learning.


  1. All data from the Bureau of Justice Statistics.
  2. https://www.fbi.gov/services/cjis/ucr/nibrs
  3. I’m indebted to my friend Se-Hyoung Yi for his review and feedback on this article and for reminding me to emphasize the drawbacks and changes coming to UCR.