Annex B - Sources of information, data quality and confidentiality, and revisions
Sources of information
B1 Information presented in this bulletin is based on data held in the Scottish Offenders Index ( SOI), which is derived from the data used in the Criminal Proceedings in Scotland statistical bulletin. The Criminal Proceedings data is in turn derived from information held on the Criminal History System ( CHS) which is owned by Police Scotland.
B2 The SOI currently contains a record of criminal proceedings against individuals (excluding companies) in Scottish courts as well as information on non-court disposals. The data in the SOI currently covers all convictions where a sentence was imposed since the beginning of 1989, and the main offence involved was either a crime in Groups 1-5, or some of the offences in Group 6, in the Scottish Government's classification of crimes.
B3 The distinction between crimes and offences is made only for statistical reporting purposes. Although the violations allocated under "crimes" tend to be more serious there are some "offences" that have more severe punishments associated with them e.g. drink driving is classified under "offences" in the "motor vehicle offences" section rather than under "crimes". Groups 1-5 of the Scottish Government's classification covers non-sexual crimes of violence, sexual crimes, crimes of dishonesty, fire-raising, vandalism etc. and other crimes. The offences in Group 6 which are included in the SOI are: common assault, breach of the peace, threatening or abusive behaviour, offence of stalking, offensive behaviour at football and threatening communications (under the Offensive Behaviour at Football and Threatening Communication Scotland Act 2012), racially aggravated harassment or conduct, miscellaneous firearms offences, and social security offences. See Annex Table A2 for a more detailed list of the types of crimes in the SOI.
B4 Each record on the SOI database includes information on the sex and date of birth of the offender, the dates of conviction and sentence, the main offence involved and details of the sentence imposed. Information is also available on any offences which were additional to the main offence involved. Each offender has a unique reference number, which allows individual convictions for that offender to be linked together. The SOI is a statistical database and does not include personally identifiable information.
B5 Not all convictions in the Scottish courts are included on the SOI. Crime types for minor offences (such as drunkenness, and almost all motor vehicle offences) are not included. The SOI contained information going back to 1989.
B6 All but the most serious offences alleged to have been committed by children under the age of 16 are generally dealt with by the children's hearings system. The SOI does not currently hold information on offenders' juvenile offending history.
B7 The figures in the bulletin have been derived from administrative IT systems which, as with any large scale recording system, are subject to possible errors with data entry and processing. During the production of this bulletin we have put in place processes to ensure that the data are fit for purpose for this publication, which are listed below.
B8 Data standards are adhered to by organisations inputting data to the CHS in terms of the definitions of data items and their corresponding values. These standards are agreed under the Justice Digital Strategy and ensure there is consistency across the justice organisations in the information they collect. Further information on the data standards can be found here.
B9 The following protocols also ensure consistency in the data collected:
- The Scottish Courts and Tribunal Service protocol for the handling of errors that may occur in the transmission of data between justice partners‟ databases;
- The protocol for the investigation/resolution of disputed data between Police Scotland and the Crown Office and Procurator Fiscal Service;
- The protocol for sharing electronic information between justice partners.
Further information on these protocols can be seen here.
B10 The Scottish Government also has representation on a data quality group and is kept informed of any data quality issues relating to the CHS. This group meets around three times a year and has representation from Police Scotland, COPFS, Scottish Prison Service and Scottish Courts and Tribunals Service.
B11 The Scottish Government also has representation on a data quality group and is kept informed of any data quality issues relating to the CHS. This group meets around three times a year and has representation from Police Scotland, COPFS, Scottish Prison Service and Scottish Courts and Tribunals Service.
B12 The analyses in this bulletin are based on the data published in the Criminal Proceedings in Scotland statistical bulletin, and the quality assurance process is described in the section on Data quality: Data validation during production of the statistical bulletin Annex B of the Criminal Proceedings bulletin. In summary, the validation processes include automated and manual checks on the data. Any unusual or missing values are referred back to either Police Scotland, the Scottish Court Service ( SCS), or the Crown Office and Procurator Fiscal Service ( COPFS). The figures are also checked against case processing information published by COPFS and management information provided by SCS to ensure that the court volumes are consistent. Police Scotland, SCS, COPFS and policy experts within the Scottish Government are also consulted to give insight on an operational level and provide insight into why any significant changes may have occurred. The figures are also checked by Scottish Government statisticians, who have not been involved in the production process, and they may highlight any issues that may have gone unnoticed.
B13 During the production of this bulletin, the data undergoes processing to calculate the frequency and prevalence of reconvictions. The numbers are manually checked to determine whether there are any unusual values, and if so, then the calculations are rechecked. Like the Criminal Proceedings in Scotland publication, the new figures in this bulletin have undergone a further round of checks by Scottish Government statisticians, and policy experts within the Scottish Government are again consulted to provide insight and context to any significant changes in the figures.
B14 Court proceedings are held in public and may be reported on by the media unless the court orders otherwise, for example where children are involved.
While our aim is for the statistics in this bulletin to be sufficiently detailed to allow a high level of practical utility, care has been taken to ensure that it is not possible to identify an individual or organisation and obtain any private information relating to them.
B15 We have assessed the risk of individuals being identified in the tables in this bulletin and have established that no private information can be identified. Where demographic information is provided this is done in wider categories of ages. This ensures that where there are small numbers, individuals can not be identified.
B16 Some of the additional data tables we provide alongside this publication have local authority information related to the offender. In the Local Authority tables, either demographic information is provided or offence-level information is provided, but not a combination of both. Similar to the main publication tables demographic information is divided into wider age categories to further ensure no information about individuals can be extracted from these tables.
B17 In terms of security and confidentiality of the data received from the data suppliers, only a small number of Scottish Government employees have access to the datasets outlined in the various stages of processing outlined above. The only personal details received by the Scottish Government in the data extract are those which are essential for the analyses in this bulletin.
B18 The CHS is not designed for statistical purposes. It is dependent on receiving timely information from the SCS, COPFS, and the police. It should also be noted that some types of outcome are removed from the system after a prescribed length of time. A pending case on the CHS is updated in a timely manner, but there are occasions when a slight delay may happen. Recording delays of this sort generally affect high court disposals relatively more than those for other types of court. The figures provided in this bulletin reflect the details of court proceedings recorded on the CHS and supplied to the Scottish Government by the end of September 2016 to allow later convictions for 2015-16 to be captured on the CHS.
B19 The CHS is regularly updated, so subsequent analyses will result in revised figures (shown in Annex Table B1) as late records are added. The first revision of the reconviction rate in the following year's bulletin is typically 0.4 percentage points higher than the figures published initially, and the average number of reconvictions per offender is typically 0.01 to 0.02 higher.
Table B1 Revisions to reconviction rates
1st revision of
2nd revision of
3rd revision of
|Reconv. rate||Av. no. of reconvs. per offender||Reconv. rate||Av. no. of reconvs. per offender||Reconv. rate||Av. no. of reconvs. per offender||Reconv. rate||Av. no. of reconvs. per offender|
|2006-07||32.2||0.59* †||32.4||0.60* †||32.4||0.60 †||32.4||0.60 †|
|2007-08||30.9||0.56* †||31.2||0.57 †||31.3||0.57 †||31.2||0.57 †|
|2008-09||31.0||0.58 †||31.5||0.60 †||31.5||0.60 †||31.5||0.60|
|2009-10||30.1||0.54 †||30.5||0.56 †||30.6||0.56||30.6||0.56|
|2010-11||28.4 X||0.50 †X||30.1 X||0.55 X||30.1||0.55||30.1||0.55|
* These figures were not published initially, but it is possible to determine their magnitude retrospectively.
† These figures have been previously reported as the reconviction frequency rate, which was the number of reconvictions per 100 offenders. Therefore these figures are the original figure divided by 100 to get the average number of reconvictions per offender.
X From the 2011-12 bulletin, some new offences that came into effect from 2010 were included in calculations for the reconviction rate and the average number of reconvictions. These offences weren't included in calculations in the 2009-10 or 2010-11 cohort bulletins. The increase in the numbers after revision led to a slightly higher increase at the 1st revision for the 2010-11 cohort than it had been in previous and subsequent years. See note in Annex B13.
B20 Since the last publication it was identified that the Early and Effective Interventions ( EEIs) statistics were underestimated as not all codes used to record them on the CHS were picked up. EEI practices vary greatly by local authority with different areas using different combinations of codes. After consultation with Police Scotland, we have included two more CHS codes and it is felt that by including these we are now providing a fuller measure of EEI activity.
B21 The inclusion of these new codes has meant that EEI figures presented in last year's bulletin have now been revised. The table below compares the differences as a result of these revisions and shows that in absolute number more offenders are now included, it also shows that the reconviction rate and average reconvictions have been revised down.
Table B2 Revisions to EEI reconviction rates
|Revised and new figures|
|Number of offenders||Reconv. rate||Av. no. of reconvs. per offender||Number of individuals||Reconv. rate||Av. no. of reconvs. per offender|
Email: Mariken Schipper
Phone: 0300 244 4000 – Central Enquiry Unit
The Scottish Government
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