Data sources: further information

For detailed information about the statistical sources used here, refer to the User Guide to Crime Statistics for England and Wales (ONS, 2016¹).

Notes:

1. This User Guide is the standard source of information on both police recorded crime figures and the CSEW.

The Crime Survey for England and Wales (CSEW) is a face-to-face victimisation survey in which people resident in households in England and Wales are asked about their experiences of a selected number of offences in the 12 months prior to the interview. It covers both children aged 10 to 15 and adults aged 16 and over, but does not cover those living in group residences (such as care homes, student halls of residence and prisons), or crimes against commercial or public sector bodies. Respondents are interviewed in their own homes by trained interviewers using a structured questionnaire that is administered on a laptop computer using specialist survey software. The questions asked do not use technical terms or legal definitions, but are in plain English.

The information collected during the interview is later reviewed by a team of specialist coders employed by the survey contractors (currently TNS-BMRB) who determine whether or not what was reported amounts to a crime in law and, if so, what offence has been experienced. This “offence coding” aims to reflect the Home Office Counting Rules for recorded crime that govern how the police record offences reported to them.

Since it began, the CSEW has been conducted by an independent (from government or the police) survey research organisation using trained interviewers to collect data from sampled respondents. The interviewers have no vested interest in the results of the survey. For the crime types and population groups it covers, the CSEW has a consistent methodology and is unaffected by changes in levels of public reporting to the police, recording practice or police activity. As such, the survey is widely seen to operate as an independent reality-check of the police figures. The independence of the survey has been further strengthened by the transfer of responsibility from the Home Office to ONS in April 2012.

The CSEW is able to capture all offences experienced by those interviewed, not just those that have been reported to, and recorded by, the police. It covers a broad range of victim-based crimes experienced by the resident household population. However, the CSEW has necessary exclusions from its main count of crime (for example, homicide, crimes against businesses and other organisations, and drug possession). The survey also excludes sexual offences from its main crime count given the sensitivities around reporting this in the context of a face-to-face interview. However, at the end of the main interview there is a self-completion set of questions (where respondents record their responses directly onto a computer), where adults aged 16 to 59 are asked about their experience of domestic abuse and sexual violence, and these results are reported separately.

Since the survey started in 1982 (covering crime experienced in 1981) a core module of victimisation questions has asked about a range of offences experienced either by the household (such as burglary) or by the individual respondent (such as robbery). The methodologies employed have remained unchanged since the survey started enabling a consistent measure of crimes committed against individuals to be created over the last 30 years. One such methodology involves the estimates only including the first 5 incidents in any series of repeat crimes in order to ensure that estimates are not affected by respondents who report an extremely high number of crimes which may be variable between years. With recent attention placed on this methodology(with only the first 5 incidents included), we have initiated a programme of work to investigate the effect of the methodology on a range of crime types and whether increasing the number of incidents counted would improve the estimates. Further information on the programme of work being conducted by us in relation to this is available in the methodological note ‘ High frequency repeat victimisation in the Crime Survey for England and Wales (100.1 Kb Pdf) '

Since the survey is based on a sample of the population, estimates have a margin of quantifiable and non quantifiable error associated with them. Non quantifiable includes:

• when respondents have recalled crimes in the reference period that actually occurred outside that period (“telescoping”)

• crimes that did occur in the reference period that were not mentioned at all (either because respondents failed to recall a fairly trivial incident or, conversely, because they did not want to disclose an incident, such as a domestic assault)

• respondents saying they reported a crime to the police when they did not (a “socially desirable” response)

• some incidents reported during the interview being miscoded (“interviewer/coder error”)

The CSEW has a nationally representative sample of around 35,000 adults and 3,000 children (aged 10 to 15 years) per year. The response rates for the survey in the year ending March 2015 were 70% and 60% respectively. The survey is weighted to adjust for possible non-response bias and to ensure the sample reflects the profile of the general population. Being based on a sample survey, CSEW estimates are subject to a margin of error. Unless stated otherwise, all changes in CSEW estimates described in the main text are statistically significant at the 95 per cent level. For more information on statistical significance and confidence intervals for CSEW data, see Section 8 of the User Guide to Crime Statistics for England and Wales (ONS, 2016).

Data from the Crime Survey for England and Wales (CSEW) continue to be badged as National Statistics.

In accordance with the Statistics and Registration Service Act 2007, statistics based on police recorded crime data have been assessed against the Code of Practice for Official Statistics and found not to meet the required standard for designation as National Statistics¹. The full assessment report can be found on the UK Statistics Authority website.

Police recorded crime figures are supplied by the 43 territorial police forces of England and Wales, plus the British Transport Police, via the Home Office, to ONS. The coverage of police recorded crime is defined by the Notifiable Offence List², which includes a broad range of offences, from murder to minor criminal damage, theft and public order offences. However, there are some, mainly less serious offences, that are excluded from the recorded crime collection. These ‘non-notifiable’ crimes include many incidents that might generally be considered to be anti-social behaviour, but that may also be crimes in law (including by-laws) such as littering, begging and drunkenness. Other non-notifiable offences include driving under the influence of alcohol, parking offences and TV licence evasion. These offences are not covered in either of the main 2 series and are separately reported on in this release to provide additional context.

Police recorded crime is the primary source of sub-national crime statistics and for relatively serious, but low volume, crimes that are not well measured by a sample survey. It covers victims (including, for example, residents of institutions and tourists as well as the resident population) and sectors (for example, commercial bodies) excluded from the CSEW sample. Recorded crime has a wider coverage of offences, for example covering homicide, sexual offences, and crimes without a specific, identifiable victim (referred to as “other crimes against society”) not included in the main CSEW crime count. Police recorded crime also provides good measures of well-reported crimes, but does not cover any crimes that are not reported to, or discovered by, the police. It is also affected by changes in reporting and recording practices. Like any administrative data, police recorded crime will be affected by the rules governing the recording of data, by the systems in place, and by operational decisions in respect of the allocation of resources.

As well as the main police recorded crime series, there are additional collections providing detail on offences involving the use of knives and firearms, which are too low in volume to be measured reliably by the CSEW.

During 2014, Her Majesty’s Inspectorate of Constabulary (HMIC) carried out a national inspection of crime data integrity. Audits of crime and incident data were carried out between December 2013 and August 2014, looking at crimes recorded between November 2012 and October 2013 across all 43 police forces in England and Wales.

The final report on findings from the HMIC inspections, ‘Crime-recording: making the victim count’, was published on 18th November 2014 and separate crime inspection force reports for each of the 43 police forces in England and Wales were published on 27th November 2014. HMIC concluded that, across England and Wales as a whole an estimated one in five offences (19%) that should have been recorded as crimes were not. The greatest levels of under-recording were seen for violence against the person offences (33%) and sexual offences (26%), however there was considerable variation in the level of under-recording across the different offence types investigated (for example, burglary; 11%).

The report outlines several recommendations to strengthen recording practices in forces. More detail can be found in the User Guide.

Notes for Police recorded crime

1. The full assessment report on Crime Statistics in England and Wales can be found on the UK Statistics Authority website.

2. For more details see the ‘Future dissemination strategy for the publication of National Statistics on Crime in England and Wales’.

The Home Office Homicide Index is a database which contains detailed record-level information including victim and suspect details and the circumstances of the offence, for each homicide recorded by police in England and Wales. It is continually updated with revised information from the police and the courts and, as such, is a richer source of data than the main recorded crime dataset. Data presented in this release therefore differ slightly from the homicide figures presented in the Crime in England and Wales quarterly releases.

While the Homicide Index is covered by the de-designation of all data based on police recorded crime, Home Office and ONS statisticians do not have significant concerns about the accuracy of recording of homicides. However, ONS accepts that there is currently insufficient evidence to provide that assurance. The ONS will work with partners to obtain fuller information on the quality of the Homicide Index and will request a re-assessment by the UK Statistics Authority in due course.

Information is available from the police on whether a firearm is used during any recorded notifiable offence. If a firearm had been used, the Home Office receive additional data about the circumstances of that offence. Offences involving the use of firearms relate to any crime recorded by the police where a firearm has been discharged, used as a blunt instrument or in a threat. Firearm possession offences, where the firearm has not been used, are not included. Firearms covered by the Firearms Act 1968 include handguns, shotguns, rifles, imitation weapons, air weapons and some other weapon types such as CS gas and pepper sprays.

Since January 2009, the Crime Survey for England and Wales (CSEW) has asked children aged 10 to 15 resident in households in England and Wales about their experience of crime in the previous 12 months. The questionnaire has been refined since its inception with the most recent data published in Crime in England and Wales, year ending September 2015. Violence accounts for a large proportion of the crimes experienced by 10 to15 year olds. Methodological differences mean that direct comparisons cannot be made between the adult and child data (Millard and Flatley, 2010).Children are not asked the questions about intimate violence reported that are reported on in Chapter 4 of this release.