The Recorded Crime Detection 2018 statistical publication provides a snapshot of the extent to which crimes reported to An Garda Síochána in 2018 have been detected. For a crime to be marked as detected at least one suspected offender must be identified and sanctioned. The publication is based on data recorded by An Garda Síochána on its PULSE (Police Using Leading Systems Effectively) and FCPS (Fixed Charge Penalty System) databases.

CSO has not published statistics on crime detection in Ireland since 2016 for reference year 2014. The decision to resume publication of crime detection statistics now is based on ongoing demand for these statistics from users and, importantly, in response to new data governance controls introduced by An Garda Síochána specifically targeted at improving data quality in the recording of detections. The background notes to this publication contains more details in relation to these quality improvements: Background Notes

The new governance controls support more reliable data outputs. It is important for users to understand, however, that the improved data quality constitutes a significant break-in-series for measuring crime detection rates in Ireland. Therefore 2018 detection rates published today cannot be compared with figures published from before this change.

The break-in-series occurred during Q1 2018, so figures published for 2018 will include a portion of the year where the old system was in use. It will be important for users to consider this when comparing future years with 2018. CSO will ensure that users are reminded of this when it becomes relevant.

For a crime to be marked as detected, at least one suspected offender must be identified and sanctioned. Valid sanctions include charge or summons, formal and informal cautions (e.g. Adult Caution, Juvenile Caution), and fixed penalties (e.g. Fixed Charge Notice, Fixed Penalty Notice) for certain offences. There are some limited circumstances where a detection is allowed but a suspected offender is not sanctioned, e.g. the offender dies before they can be prosecuted, or the Director of Public Prosecutions (DPP) decides that prosecution is not in the public interest. These circumstances are outlined in the An Garda Síochána Crime Counting Rules document.

There are various circumstances where a crime is not considered detected, for instance an investigation has not identified a suspected offender, or there is insufficient evidence to support a prosecution.

The time lag between an offence being recorded and a suspected offender being formally sanctioned is influenced by a variety of factors e.g. gathering evidence, awaiting laboratory results or a direction for prosecution. As such, detection rates are a point-in-time measurement (i.e. when the data was extracted) and increase over time as more investigations are completed. This affects some crime types more than others.

The gap between the end of the reporting period and when data is extracted from PULSE for the purpose of compiling statistics influences detection rates. The data used to compile these statistics was extracted on 2 September 2019.

CSO continues to publish recorded crime statistics using the category 'Statistics Under Reservation'. This category is used to reflect ongoing concerns regarding the quality of the data source. See: Statistics Under Reservation FAQs 

Detection rates vary by crime type

The proportion of crime incidents reported in 2018, which were marked detected by the beginning of September 2019, varies considerably by crime incident type, from a high of 85% of recorded incidents in Group 10 (Controlled drug offences) to a low of 11% of recorded incidents in Group 02 (Sexual offences). See Tables 1.1 and 3.1.