Reconviction Rates in Scotland: 2020-21 Offender Cohort

7. Comparing reconviction rates across local authorities

(Table 12)

7.1 Estimating reconviction rates for local authorities

In Reconviction rates in Scotland, we historically only published reconviction rates for local authorities based on information for offenders convicted in courts that fall within that local authority area’s boundary. This is because it was the only information on local authority that we could obtain. However, the areas that courts serve do not exactly match local authorities; and offenders may be convicted in a court located in a different administrative area to where they live, yet they would be supervised in their area of residence (see Annex A12 and the footnote of Table 12). The characteristics of offenders are also likely to vary across local authority areas, therefore such comparisons between areas should be treated with caution, and it is suggested that a method which takes these factors into account should be employed (see section 3.1).

To improve estimates of reconviction rates for local authorities, we started to collect data on the first half of an offender’s home postcode from Police Scotland, for example EH1 or G1. This data can then be used to match an offender to their home local authority. This information will be particularly important for local authorities who use these statistics for planning purposes, such as schemes to reduce reoffending, or estimating the number of offenders that social workers need to supervise in their area. Local authority reconviction rates based on offender postcodes are published for the third time this year, but due to incomplete postcode coverage, we will still publish reconviction rates based on court area until it improves. We recommend that the figures based on court area are still used as the definitive local authority reconviction rates.

7.2 Local authority reconviction rates based on court area

Reconviction rates vary across local authority groups (based on the area covered by courts). Note that because some sheriff courts cover more than one local authority, we cannot distinguish between convictions in the different local authorities. Therefore some local authorities are grouped together, so that there are 24 groups rather than 32 separate local authorities. Index convictions in the High Courts are presented separately from local authority groups. High Court index convictions were included in the local authority where the High Court was located prior to the 2016-17 cohort bulletin so the figures here are not comparable with earlier bulletins (see revisions in Annex B32 for further information).

Table 12 shows that the highest reconviction rate in the 2020-21 cohort was for offenders whose index conviction was given in courts in Ayrshire, East, North and South (30.3%). Dumfries and Galloway had the highest number of reconvictions per offender on average (0.48). Excluding convictions in the High Court, the lowest reconviction rate (10.6%) was given in courts in Argyll and Bute, which also had the lowest average number of reconvictions per offender (0.15). These are unadjusted figures which do not take account of underlying differences in population size and the characteristics of offenders in each area (see section 3.1 for comparisons of standardised reconviction rates which take these into account).

Reconvictions tend to fluctuate year to year for local authorities. Smaller local authorities tend to have larger fluctuations as they have small numbers of offenders. Small between-year fluctuations in the numbers of offenders reconvicted may lead to larger changes in the reconvictions in percentage terms compared to local authorities with larger numbers of offenders.

7.3 Local authority reconviction rates based on residence

Table 13 shows reconviction rates based on the local authority of offenders’ residence. This is achieved by matching the local authority to the first half of offenders’ postcodes. The local authority reconviction rates based on postcode are currently labelled as Experimental Statistics: Data being developed, as this analysis was only recently introduced and we did not have postcodes for over a tenth with an index conviction in 2020-21. Postcodes may be missing because offenders have no fixed abode, but it may also be a recording issue.

Custodial sentences have a higher percentage of missing postcodes compared to other sentences. This may relate to the personal circumstances of those given custodial sentences. This is not surprising as many custodial sentences counted here would have been recorded on the CHS before Police Scotland started sending us conviction data with postcode information.

Note that the data quality issues around the recording of postcodes only affects the local authority reconviction rates presented in Table 13 and does not affect any of the other reconviction rates presented in this publication.

Annex Table B1 shows the number and percentage of offenders with missing postcodes in each local authority group, based on the location of the court they were convicted in. It also shows the percentage of offenders living in the local authorities that are covered by the court areas, and the percentages that live in different local authorities to those covered by the court areas.

Annex Table B1 shows there is variation in the percentages of missing postcodes between local authorities, so direct comparisons between local authorities should be treated with caution. The missing data may mean that the reconviction rates are over or underinflated, but we do not have enough information to know fully know the effects of the missing data on the rates. Also, different local authorities may have different mixes of offender characteristics, and small local authorities may experience greater fluctuations, which should be considered when comparing local authorities. The next section discusses these considerations in more detail (although those comparisons of local authorities are based on court area, the same factors would apply here).