UCR Frequently Asked Questions

Frequently Asked Questions (FAQs) General Information

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All textual references are to the UCR Handbook (pdf) (2004) unless otherwise noted.


What is the UCR Program?

The UCR Program is a voluntary city, university and college, county, state, tribal, and federal law enforcement program that provides a nationwide view of crime based on the submission of statistics by law enforcement agencies throughout the country.

When and how was the Program implemented?

In the 1920s, the International Association of Chiefs of Police (IACP) recognized the potential value in tracking national crime statistics. The Committee on Uniform Crime Records of the IACP developed and initiated this voluntary national data collection effort in 1930.  (The IACP continues to advise the FBI on the UCR Program’s policies.)  Also in 1930, the IACP was instrumental in gaining congressional approval which authorized the FBI to serve as the national clearinghouse for statistical information on crime.  In June 1966, the National Sheriffs’ Association (NSA) established a Committee on Uniform Crime Reporting to serve in an advisory capacity and to encourage sheriffs throughout the country to fully participate in the Program.  Since 1930, through the UCR Program, the FBI has collected and compiled data to use in law enforcement administration, operation, and management, and to indicate fluctuations in the level of crime in America.

For which categories (e.g., penal, prosecution, arrest, conviction) are statistics collected through the UCR Program?

To best depict total crime and to provide the most meaningful data to police administrators, the UCR Program collects data on known offenses and persons arrested by law enforcement agencies.  The UCR Program does not record or collect statistics on the findings of a court, coroner, jury, or the decision of a prosecutor.

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Which specific crimes are reported to the UCR Program, and why were these crimes identified for reporting?

The UCR Program collects offense information for murder and nonnegligent manslaughter, forcible rape, robbery, aggravated assault, burglary, larceny-theft, motor vehicle theft, and arson. These are Part I offenses and are serious crimes by nature and/or volume.  Not all crimes, such as embezzlement, are readily brought to the attention of the police.  Also, some serious crimes, such as kidnapping, occur infrequently. Therefore, the UCR Program limits the reporting of offenses known to the eight selected crime classifications because they are the crimes most likely to be reported and most likely to occur with sufficient frequency to provide an adequate basis for comparison.

Arson was not originally part of the crime reporting process.  Arson became the eighth Part I crime as the result of a limited congressional mandate in October 1978.  With the passage of the Anti-Arson Act of 1982, Congress permanently designated arson as a reportable offense.

As for arrest information, the UCR Program collects arrest data on Part I offenses and 21 other crimes, such as driving under the influence, that are Part II offenses. Simple assault is a Part II offense but is collected under 4e (Other Assaults–Simple, Not Aggravated) as a quality control matter and for the purpose of looking at total assault violence.

I was looking in a table in Crime in the United States and did not see a column to list my city’s Crime Index. Why?

In June 2004, the CJIS Advisory Policy Board (APB) approved discontinuing the use of the Crime Index in the UCR Program and its publications and directed the FBI publish a violent crime total and a property crime total. The Crime Index, first published in Crime in the United States in 1960, was the title used for a simple aggregation of the seven main offense classifications (Part I offenses) in the Summary reporting system.  The Modified Crime Index was the number of Crime Index offenses plus arson.

For several years, the CJIS Division studied the appropriateness and usefulness of these indices and brought the matter before many advisory groups including the UCR Subcommittee of the CJIS APB, the Association of State UCR Programs, and a meeting of leading criminologists and sociologists hosted by the Bureau of Justice Statistics. In short, the Crime Index and the Modified Crime Index were not true indicators of the degrees of criminality because they were always driven upward by the offense with the highest number, typically larceny-theft.  The sheer volume of those offenses overshadowed more serious but less frequently committed offenses, creating a bias against a jurisdiction with a high number of larceny-thefts but a low number of other serious crimes such as murder and forcible rape.

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Is UCR participation mandatory?

No.  Participation is voluntary.

To what extent are crime statistics reported to the UCR Program?

In 2007, law enforcement agencies active in the UCR Program represented more than 285 million United States inhabitants—94.6 percent of the total population.

How can I find out how my city compares to other cities?

Each year when Crime in the United States is published, some entities use reported figures to compile rankings of cities and counties.  These rough rankings provide no insight into the numerous variables that mold crime in a particular town, city, county, state, or region.  Consequently, they 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.  The data user is, therefore, cautioned against comparing statistical data of individual reporting units from cities, metropolitan areas, states, or colleges or universities solely on the basis of their population coverage or student enrollment.  “Variables Affecting Crime” in Crime in the United States has more information on this topic.

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How can I find out what statistics and publications the UCR Program has available for public use?

Several UCR Program publications, such as Crime in the United States, Law Enforcement Officers Killed and Assaulted, and Hate Crime Statistics are available on the UCR Program’s pages of the FBI Internet site at www.fbi.gov/ucr/ucr.htm.  Data are also available by contacting the Multimedia Productions Group, Criminal Justice Information Services Division, Federal Bureau of Investigation, Module D3, 1000 Custer Hollow Road, Clarksburg, West Virginia 26306-0157; telephone (304) 625-4995; facsimile (304) 625-5394; e-mail cjis_comm@leo.gov. (E-mail requests must include the requester’s contact information, such as name, address, and telephone number.)

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Why and how are offenses estimated for publication in Crime in the United States?

Tables 1 through 5 and Table 7 of Crime in the United States contain statistics for the entire United States.  Because not all law enforcement agencies provide data for complete reporting periods, the FBI includes estimated crime numbers in these presentations.  The FBI estimates data for three areas: Metropolitan Statistical Areas (MSAs), cities outside MSAs, and nonmetropolitan counties.  The FBI computes estimates for participating agencies not providing 12 months of complete data. For agencies supplying three to 11 months of data, the national UCR Program estimates for the missing data by following a standard estimation procedure using the data provided by the agency. If an agency has supplied less than three months of data, the FBI computes estimates by using the known crime figures of similar areas within a state and assigning the same proportion of crime volumes to nonreporting agencies. The estimation process considers the following:  population size covered by the agency; type of jurisdiction, e.g., police department versus sheriff’s office; and geographic location.

How does the UCR Program compute agency populations?

To more accurately reflect an agency’s population, the national UCR Program has changed the methodology for estimating populations.  In the past, the FBI calculated state growth rates using revised state/national population estimates from the previous year and provisional state/national population estimates provided by the U.S. Census Bureau. The FBI then estimated population figures for city and county jurisdictions by applying the state growth rate for the current year to the updated U.S. Census Bureau data.

However, beginning with the 2007 edition of Crime in the United States, the FBI computed individual rates of growth from one year to the next for every city/town and county using 2000 decennial population counts and 2001 through 2006 population estimates from the U.S. Census Bureau.  Each agency’s rates of growth were averaged; that average was then applied and added to its 2006 Census population estimate to derive the agency’s 2007 population estimate.

More information on how the national UCR Program determines population is available in the “Methodology” of Crime in the United States, 2007.

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The UCR Program details reported crime. Is there any program in operation which attempts to address unreported crime?

Yes.  The U.S. Department of Justice’s National Crime Victimization Survey (NCVS) estimates the number of unreported serious crimes nationwide.  The Internet address for the Bureau of Justice Statistics, which conducts the NCVS, is www.ojp.usdoj.gov/bjs.

How do UCR and NCVS differ?

The UCR Program and the NCVS were designed to complement each other.  The UCR Program provides a reliable set of criminal justice statistics for law enforcement administration, operation, and management, as well as to indicate fluctuations in the level of crime in America.  The NCVS provides previously unavailable information about victims, offenders, and crime (including crime not reported to the police).  The two programs employ different methodologies, but they measure a similar subset of serious crimes.  Both programs cover forcible rape, robbery, aggravated assault, burglary, theft, and motor vehicle theft.  Both the UCR and the NCVS have similar definitions of forcible rape, robbery, and theft.

How can I compare the UCR Program’s findings with that of the NCVS?

Users should not compare crime trends in the UCR Program and the NCVS because of methodology and crime coverage differences.  The programs examine the nation’s crime problem from different perspectives, and their results are not strictly comparable.  Definitional and procedural differences can account for many apparent discrepancies in results from the national Program.  For example, the NCVS includes crimes reported and not reported to law enforcement; the UCR Program includes only those crimes reported to police.  The NCVS rates property crimes per 1,000 households, and the UCR Program rates these crimes per 100,000 inhabitants. Also, the BJS derives NCVS estimates from interviewing a sample and are, therefore, subject to a margin of error.  The UCR Program bases its data on the actual counts of offenses reported by law enforcement agencies.  Additional information about the differences between the two programs is in “The Nation’s Two Crime Measures” in Crime in the United States.

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What are classifying and scoring?

Classifying is determining the proper crime category in which to report an offense to the UCR Program. Scoring is counting the number of offenses after they have been classified and entering the total count on the appropriate reporting form. 

Classifying and scoring offenses are the two most important functions that a participant in the UCR Program performs.  The data that contributing agencies provide are based on these two functions, so scrupulous attention to the Program’s guidelines helps to ensure accurate and reliable data (p. 7).

What is the Hierarchy Rule?

The Hierarchy Rule:  “...when more than one Part I offense is classified, the law enforcement agency must locate the offense that is highest on the hierarchy list and score that offense involved and not the other offense(s) in the multiple-offense situation” (p. 10).

The Hierarchy Rule, which requires counting only the highest offense and ignoring all others, applies only to the crime reporting process and does not affect the number of charges for which the defendant may be prosecuted in the courts.

Are there exceptions to the Hierarchy Rule?

Yes.  “The offenses of justifiable homicide, motor vehicle theft, and arson are exceptions to the Hierarchy Rule” (p. 10).

What is an exceptional clearance?

In certain situations, law enforcement is not able to clear an offense known to them by making an arrest (see Cleared by Exceptional Means, p. 80).  Often they have exhausted all leads and have done everything possible in order to clear a case.  If agencies can answer all of the following questions in the affirmative, they can clear the offense exceptionally for the purpose of reporting to UCR.

  • Has the investigation definitely established the identity of the offender?
  • Is there enough information to support an arrest, charge, and turning over to the court for prosecution?
  • Is the exact location of the offender known so that the subject could be taken into custody now?
  • Is there some reason outside law enforcement control that precludes arresting, charging, and prosecuting the offender?  (pp. 80-81).

For UCR reporting purposes, can a male be raped?

No.  The UCR Program defines forcible rape as “The carnal knowledge of a female forcibly and against her will” (p. 19).  In addition, “By definition, sexual attacks on males are excluded from the rape category and must be classified as assaults or other sex offenses depending on the nature of the crime and the extent of injury” (p. 20).  An aggravated assault is a Part I offense and would be reported on the Return A form. (A simple assault is a Part II offense but also would be reported on the Return A form.)  Sex offenses qualify as Part II offenses and would be reported on the appropriate Age, Sex, and Race of Persons Arrested form (pp. 96 and 142).

However, in the National Incident-Based Reporting System (NIBRS), a sexual assault on a male by a female could be classified as a forcible rape, depending on the nature of the attack and the extent of the injury.  For NIBRS reporting purposes, forcible rape is defined as “The carnal knowledge of a person, forcibly and/or against that person's will; or not forcibly or against the person's will where the victim is incapable of giving consent because of his/her temporary or permanent mental or physical incapacity (or because of his/her youth)” (UCR Handbook, NIBRS edition, 1992, p. 21). In the NIBRS, at least one offender must be of a different sex than the victim for the event to be classified as a forcible rape. For example, a female can rape a male, or in the case of multiple offenders, a female and male can rape a male.  However, a male cannot rape another male, or in the case of multiple offenders, two males cannot rape a male.

The NIBRS provides greater specificity in crime reporting. The UCR Summary reporting system collects most of its crime data in the form of categories.  The NIBRS has a greater ability to capture and breakdown data into specific subcategories through the use of revised and new offense definitions.

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Frequently Asked Questions
April 2009


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