In Ireland, an offence is recorded in the crime statistics when there is a reasonable probability that a criminal offence took place and there is no credible evidence to the contrary. This is important as how crimes are recorded can influence crime statistics. For example, Sweden records all reported suspected crimes in its crime statistics even though some may later be found not to be criminal offences. In addition, how crimes are processed and counted can also have an impact on crime statistics, suggesting that caution may be required when attempting to compare Irish crime statistics to those available in other countries. For instance, in collecting their statistics, An Garda Síochána (the Irish Police Force) employ the 'primary (or principal) offence rule'. In other words, when two or more criminal offences are disclosed in a single episode it is the 'primary' or most serious offence that is counted only. As an example, if an individual commits an assault while drunk and disorderly, only the assault (most serious offence) is counted in the crime statistics, although the individual has also committed a public order offence (less serious offence) as a result of being drunk and disorderly in public. As no international standards on how crime statistics should be produced and presented are available, it is difficult to make comparisons between countries as the methods used to record and count crime statistics vary from country to country. Nonetheless, for those interested in broader European trends, Eurostat - The Statistical Office of the European Communities - is responsible for collecting, analysing and comparing information on crime and victimisation across EU Member States.
It is important to note that Irish crime statistics reflect the number of offences coming to the attention of An Garda Síochána (the Irish Police Force) and do not take account of the number of crimes committed which are not reported to An Garda Síochána. This is known as the ‘dark figure’ of crime and is a primary reason why official crime statistics are often supplemented by 'crime and victimisation' surveys. In Ireland, the Garda Public Attitudes Survey and the Crime and Victimisation component of the Quarterly National Household Survey, conducted by the Central Statistics Office, may be used to obtain an indication of the 'dark figure' of crime.
Up until 2006, Irish crime statistics were published by An Garda Síochána. However, following a report by an expert group on crime statistics in 2004, the publication of Irish crime statistics was taken over by the Central Statistics Office. Since then, an Advisory Group has been established by the Central Statistics Office in order to assist in the development of crime and criminal justice statistics. The Director and Senior Research Officer of the National Crime Council are members of the Advisory Group. As part of the work of the Advisory Group, the distinction between Headline/ Non-Headline offences was reviewed and recommendations for a more robust classification system were put forward. On 17th April 2008, the Central Statistics Office published the new Irish Crime Classification System (ICCS) (PDF, 172 KB) the development of which was informed by the work of the Advisory Group. The first use of this new classification system occured on 23rd March and involved reclassification by the Central Statistics Office of crime statistics covering the period 2003 to 2006 (2.87 MB). For further information, please visit the Central Statistics Office website at http://www.cso.ie .
The crime figures published by An Garda Síochána and the Central Statistics Office also do not record crimes prosecuted by authorities other than An Garda Síochána such as the Revenue Commissioners, the Health and Safety Authority, the Office of the Director of Corporate Enforcement, the Department of Social and Family Affairs and the Environmental Protection Agency. A similiar situation obtains in many other countries.