Crime statistics

Crime statistics attempt to provide a statistical measure of the level, or amount, of crime that is prevalent in societies. Given that crime, by definition, is an illegal activity, every way of measuring it is likely to be inaccurate.

There are many forms of measuring crime, including household surveys or checking hospital or insurance records, but the term "crime statistic" usually refers to figures compiled by the Police and similar law enforcement agencies. However, it is well known that many if not most offences are not reported to the police, and changes in police procedures can have a big impact on how such reported crims are categorised. This is why public surveys are sometimes conducted to estimate the amount of crime not reported to police and to ascertain levels of victimisation. Such surveys are usually more reliable in providing reliable trends over time, but they rarely ecompass all crime (eg separate surveys are required to measure retail crime such as shoplifting, as distinct from crime against the public), rarely give local statistics useful for local crime prevention or enforcement, often ignore offences against children, and do not count offenders brought before the criminal justice system.

Crime statistics are gathered and reported by many countries and are of interest to several international organisations, including Interpol and the United Nations. Law enforcement agencies in some countries, such as the FBI in the United States and the Home Office in England & Wales, publish crime indices, which are compilations of statistics for various types of crime.

Statistics are usually collected on

Offences - Breaches of the law
Offenders - Those who commit offences
Victims - Those who are offended against

Because laws vary between jurisictions, comparing crime statistics between, and even within, countries can be difficult, sometimes even problematic. Even overall international trends can be difficult to interpret authoritatively. Research using a series of victim surveys in 18 countries of the European Union funded by the European Commission has reported (2005) that the level of crime in Europe has fallen back to the levels of 1990, and notes that levels of common crime have shown declining trends in the U.S.A., Canada, Australia and other industrialised countries as well. The European researchers say a general consensus identifies demographic change as the leading cause for this international trend. However they suggest that "increased use of crime prevention measures may indeed be the common factor behind the near universal decrease in overall levels of crime in the Western world", since decreases have been most pronounced in property crime and less so, if at all, in contact crimes.^[1]^[2]

Recording practices

Crime statistics recording practices vary, not only between countries and jurisdictions but sometimes within jurisdictions and even between two individual law enforcement officers encountering the same situation. Because many law enforcement officers have powers of discretion, they have the ability to affect how much crime is recorded based on how they record their activities. Even though a member of the public may report a crime to a law enforcement officer, unless that crime is then recorded in a way that allows it to be incorporated into the crime statistics it will not be counted. As a consequence, offending, particularly minor offending, may be significantly undercounted in situations where law enforcement officers are overloaded with work or do not perceive the offending as worth being recorded. Similarly certain high profile categories of crime may be well reported when there is an incentive (such as a financial or performance incentive) for the law enforcement officer to do so.

For example: Almost all recorded traffic offending is reported either by law enforcement officers (or by automatic road safety cameras) because there is normally a fine and (profitable) revenue collection process to go through. Yet it is likely that very little traffic offending reported by the public will make its way into official statistics because of the difficulty in following up these reports.

Counting rules

Counting rules vary from jurisdiction to jurisdiction. Relatively few standards exist and none that permit international comparability beyond a very limited range of offences. However, many jurisdictions accept the following:

There must be a prima face case that an offence has been committed before it is recorded. That is either police find evidence of an offence or receive a believable allegation of an offense being committed.
Multiple reports of the same offence count as one offence. Some jurisdictions count each report separately.
Where several offences are committed at the same time, in one act of offending, only the most serious offense is counted. Some jurisdictions record and count each and every offense separately.
Where multiple offenders are involved in the same act of offending only one act is counted when counting offenses but each offender is counted when apprehended.
Offending is counted at the time it come to the attention of a law enforcement officer. Some jurisdictions record and count offending at the time it occurs.

Offending that is a breach of the law but for which no punishment exists is often not counted. For example: Suicide, which is technically illegal in most countries, may not be counted as a crime, although attempted suicide and assisting suicide are.

Also traffic offending and other minor offending that might be dealt with by using fines, rather than imprisonment is often not counted as crime. Although separate statistics may be kept for this sort of offending.

Notes

^ Van Dijk, J.J.M., Manchin, R., Van Kesteren, J., Nevala, S., Hideg, G. (2005). The Burden of Crime in the EU. Research Report: A Comparative Analysis of the European Crime and Safety Survey (EU ICS) 2005 accessed at [1] April 12, 2007 - pp.21-23
^ Kesteren, J. van, Mayhew, P., Nieuwbeerta, Paul (2000). Criminal victimization in seventeen industrialized countries: key findings from the 2000 International Crime Victims Survey accessed at [2] April 12, 2007 - pp.98-99

Crime statistics

Recording practices

Counting rules

Notes

Further reading

See also