Uniform Crime Reporting Survey (UCR)
Detailed information for 2008
The Uniform Crime Reporting Survey was designed to measure the incidence of crime in Canadian society and its characteristics. The information is used by federal and provincial policy makers as well as public and private researchers.
Data release - July 21, 2009
- Questionnaire(s) and reporting guide(s)
- Data sources and methodology
- Data accuracy
The Canadian Centre for Justice Statistics (CCJS), in co-operation with the policing community, collects police-reported crime statistics through the Uniform Crime Reporting Survey (UCR). The UCR Survey was designed to measure the incidence of crime in Canadian society and its characteristics.
UCR data reflect reported crime that has been substantiated by police. Information collected by the survey includes the number of criminal incidents, the clearance status of those incidents and persons-charged information. The UCR Survey produces a continuous historical record of crime and traffic statistics reported by every police agency in Canada since 1962. In 1988, a new version of the survey was created, UCR2, and is since referred to as the "incident-based" survey, in which microdata on characteristics of incidents, victims and accused are captured.
Data from the UCR Survey provide key information for crime analysis, resource planning and program development for the policing community. Municipal and provincial governments use the data to aid decisions about the distribution of police resources, definitions of provincial standards and for comparisons with other departments and provinces.
To the federal government, the UCR survey provides information for policy and legislative development, evaluation of new legislative initiatives, and international comparisons.
To the public, the UCR survey offers information on the nature and extent of police-reported crime and crime trends in Canada. As well, media, academics and researchers use these data to examine specific issues about crime.
The survey is currently administered as part of the National Justice Statistics Initiative (NJSI). Since 1981, the federal, provincial and territorial Deputy Ministers responsible for the administration of justice in Canada, with the Chief Statistician, have been working together in an enterprise known as the NJSI. The mandate of the NJSI is to provide information to the justice community as well as the public on criminal and civil justice in Canada. Although this responsibility is shared among federal, provincial and territorial departments, the lead responsibility for the development of Canada's statistical system remains with Statistics Canada.
Reference period: Calendar year
Collection period: January 1 to December 31 of reference year
- Crime and justice
- Crimes and offences
Data sources and methodology
The UCR Survey collects information only on those crimes that come to the attention of the police. The UCR data, therefore, do not contain a count of all crimes in Canada: some crimes are never detected and, of those that are, some are never brought to the attention of the police.
There are two versions of the UCR collection instrument that are operating simultaneously: UCR Aggregate (UCR1.0) Survey and the UCR2 Incident-based Survey, which is comprised of three versions, UCR2.0, UCR2.1, and UCR2.2.
The UCR Aggregate Survey (UCR1.0) collects summary data for nearly 100 separate criminal offences and has been in place since 1962.
In order to collect more detailed information on each incident, victims and accused persons, the UCR2 Survey was developed in the mid-1980's. This alternative method of data collection in which a separate statistical record is created for each criminal incident is known as an "incident-based" reporting system. The first respondent reported incident-based data in 1988.
A revised version of the UCR2 survey known as UCR2.1 was introduced in 1998. This survey introduced certain efficiencies for police services and lowered response burden by eliminating or simplifying UCR2 variables. Then, in 2004, another version named UCR 2.2 was introduced to take into account new violations/variables (not processed separately in the past) such as organized crime, cyber crime, hate crime and geocode information.
This survey is a census with a cross-sectional design.
Data are collected for all units of the target population, therefore, no sampling is done.
Data collection for this reference period: 2008-01-01 to 2008-12-31
Responding to this survey is mandatory.
Data are collected directly from survey respondents and extracted from administrative files.
Police Services are the respondents. The response rate in terms of police respondents complying with the UCR Survey is virtually 100 percent. There are more than 1,200 separate police detachments responding to the survey, comprising 204 different police forces.
Data for the aggregate survey are sent to the CCJS on survey forms or in machine-readable format. Monthly counts of aggregate crime and traffic incidents are recorded by police agencies and forwarded to the CCJS approximately two weeks after month end.
These forms are visually edited for completeness and consistency and, if necessary, follow-up telephone calls are made to the respondent for clarification and correction. The crime and traffic data are transferred to an electronic format by the Data Return Facility. All counts are verified to ensure that the information has been correctly transferred from the paper forms to the electronic format.
Data for the Incident-based Survey are collected from police records management systems by an approved extraction program and are forwarded to the CCJS in a machine-readable format with a standard record layout. Data are generally submitted to the CCJS on a monthly basis.
View the Questionnaire(s) and reporting guide(s).
UCR Aggregate Survey:
Data for the aggregate survey are processed through a set of automated edit routines to further verify the counts for internal consistency.
Error reports are produced and respondents are contacted to obtain correct information. Corrections are re-submitted for verification and updates. Master files of aggregate data are continually updated throughout the year and, in turn, are further processed when it is necessary to produce the year-end data.
Police services are expected to update submitted information if additional information becomes available (e.g., an accused has been charged for a previously reported incident). Assuming all procedures have been followed by the respondents, the UCR counts processed by the CCJS will correspond with the records maintained by police services at year-end.
UCR2 Incident-based Survey:
Prior to the data being extracted, record management systems now have a number of on-line edits that often mirror UCR internal edits. These edits assist the police service to maintain a high data quality standard for both themselves and the UCR survey.
Upon receipt of the data for the Incident-based Survey, initial data quality procedures are applied and the data are prepared for processing by the central processing system. This central processing system performs a series of intensive edits (more than 300) on these data, including duplicate record checks, logic and format error edits and imputations.
The system does not allow for errors on key variables; they will not pass the edits until they have been corrected. The outcome of the edits and imputations is documented in a series of edit reports and all processed data are stored in a database. Included in the edit reports are a summary of the number and types of records processed, a frequency count of edit failures and a listing of every record which failed an edit.
All edits are examined at the CCJS with the objective of identifying possible problems with the respondent system interface or with respondent adherence to survey data requirements. Any problems are followed up with the respondent. Edit reports are also sent to the respondents for their information and data correction.
The most significant loss of information occurs in the rare situation where a police service, because of technical or resource difficulties, is unable to submit a full year of data to the CCJS. If they had previously reported to UCR, historical imputation is done based on the same months from the most recent year for which data are available or, where applicable, five years of data are used to create a time series model for the missing data.
Imputation is used for the UCR2 Incident-based survey. The automated edits look for unexpected code values and will substitute a more meaningful code value given the information available within a variable and between variables.
Data are imputed for two reasons: one, a blank field was submitted when "not applicable" should have been selected; and two, due to an inter-field edit, deterministic imputation is performed (e.g., age will be imputed from the date of birth).
Police-reported Crime Severity Index (PRCSI):
The Police-reported Crime Severity Index (PRCSI), introduced in the spring of 2009, tracks changes in the severity of police-reported crime.
In the PRCSI, each type of offence is assigned a weight derived from actual sentences handed down by courts in all provinces and territories. More serious crimes are assigned higher weights, less serious offences lower weights. As a result, when all crimes are included, more serious offences have a greater impact on changes in the index. For a full explanation of the index and how it is calculated, consult the report "Measuring Crime in Canada: Introducing the Crime Severity Index and Improvements to the Uniform Crime Reporting Survey" (85-004-X, free).
All police services are asked to review summary data tables for completeness and accuracy and, where necessary, adjustments are made before a master file is created. These tables contain various information including a year-over-year comparison--using the current reporting year and the most recent prior year--which are examined to ensure that the percent changes reported by the CCJS are consistent with those identified by the police service. Upon completion of the verification process, and prior to final release, each police service is required to "sign off" on their data.
Comparing UCR Data with Courts and Corrections Data:
It is difficult to make comparisons between data reported by police and data from other sectors of the criminal justice system (i.e., courts and corrections). There is no single unit of count (i.e., incidents, offences, charges, cases or persons) which is defined consistently across the major sectors of the justice system. As well, charges actually laid can be different from the most serious offence by which incidents are categorized. In addition, the number and type of charges laid by police may change at the pre-court stage or during the court process. Time lags between the various stages of the justice process also make comparisons difficult.
Statistics Canada is prohibited by law from releasing any data which would divulge information obtained under the Statistics Act that relates to any identifiable person, business or organization without the prior knowledge or the consent in writing of that person, business or organization. Various confidentiality rules are applied to all data that are released or published to prevent the publication or disclosure of any information deemed confidential. If necessary, data are suppressed to prevent direct or residual disclosure of identifiable data.
More specifically, CCJS has a policy of not releasing any tables or cross-tabulations that may identify a particular victim or suspect by the specifics of an offence.
There are no names of individuals collected by the survey. Names are processed through a Parsing Algorithm (Soundex) before being submitted to the CCJS so that only a unique identifier is produced.
Revisions and seasonal adjustment
The cut-off for submission/revision of previous calendar year data is March 31st. After that time, the files are usually frozen. The Master File can change but only if the respondent requests the change and not after the data are released to the public, usually sometime in late July.
Preliminary results are not released or available to the public. They are simply used for verification purposes and for draft CCJS reports.
In actuality, the UCR crime statistics represent a subset of all crimes occurring in Canada, but are an accurate measure of the number of incidents of crime being reported to the police. The CCJS does not undertake audits of a police department's Records Unit to ensure complete and accurate reporting. Nor does the CCJS examine records which the police have processed and described as outside the scope of the survey.
Police departments, however, have established rules governing the collection of data (coding manuals) and have designated individuals with the task of verifying the reports from which the data are extracted. Local quality control measures are in effect for respondents of the aggregate and the incident-based survey to minimize the under-reporting of crime.
Legislation does affect the UCR survey by adding new Criminal Code offences or by changing the severity of those that presently exist. This can affect data comparisons over time.
The UCR Survey classifies incidents according to the most serious offence (MSO) occurring in the incident (generally the offence which carries the longest maximum sentence under the Criminal Code of Canada). In categorizing incidents, violent offences always take precedence over non-violent offences. For example, an incident involving both a breaking and entering offence and an assault is counted as an incident of assault.
As a result of the MSO scoring rule, less serious offences are under-counted by the aggregate survey. However, the incident-based survey allows up to four violations per incident, permitting the identification of lesser offences.
With the exception of British Columbia, all provinces and territories are now surveyed almost entirely under the UCR2 program.
In 2008, 155 police services in all 10 provinces and 3 territories supplied data for the complete year to the UCR2 survey and represented approximately 98% of the population of Canada. The coverage provided by these services in the 2008 database is distributed as follows: 39.2% from Ontario, 23.4% from Québec, 12.3% from British Columbia, 10.9% from Alberta, 3.6% from Manitoba, 3.1% from Saskatchewan, 2.9% from Nova Scotia, 2.3% from New Brunswick, 1.6% from Newfoundland and Labrador, 0.4% from Prince Edward Island, and approximately 0.1% from each of the 3 territories (Yukon, Northwest Territories and Nunavut).
The reader is cautioned that these data are not geographically representative at the national or provincial level. Continuity with the UCR aggregate survey data is maintained by a conversion of the incident-based data to aggregate counts at year-end.
For further information on data accuracy measures relating to specific respondents, please refer to the following document.
- Uniform Crime Reporting Survey - Concepts and Definitions
- Census Metropolitan Area Methodology (UCR)
- Legislative Influences (UCR)
- Modifications to the UCR Incident-Based Survey - UCR2.1