Proven reoffending statistics: definitions and measurement
Source: data.gov.uk (2018-05-25)

Proven Re-offending statistics. Key statistics on proven reoffending in England and Wales. It gives proven reoffending figures for offenders who were released from custody, received a non-custodial conviction at court, or received a caution or reprimand.

Proven Re-offending 
Statistics: Definitions and 
Measurement 
 
Published January 2016 

 
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Contents 
Proven re-offending statistics quarterly bulletin 
3 
Early estimates of proven re-offending statistics 
11 
Local adult re-offending statistics quarterly bulletin 
12 
Data quality 
13 
Statistical modelling and coefficients 
22 
Appendix A: List of serious offences 
23 
Appendix B: Glossary of terms 
28 
Appendix C: Comparison of the three measures of re-offending 35 
Contact details and further information 
37 

 
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Proven re-offending statistics quarterly bulletin 
Background 
The Ministry of Justice launched a statistical consultation on improvements 
to the transparency and accessibility of our information in 2010 and a 
response to the consultation was published in March 2011. One aspect of 
the consultation was the measurement of proven re-offending. Responses 
supported the proposals to move to a single framework for measuring re-
offending where adult and youth data can be provided at national and local 
levels on a consistent basis. The response to the consultation is available 
here. 
 
 
Prior to this consultation there were six different measures of proven re-
offending: 
 
 national adult proven re-offending; 
 
 local adult proven re-offending; 
 
 national youth proven re-offending; 
 
 local youth proven re-offending; 
 
 prolific and other priority offending (PPO); and 
 
 drug-misusing proven offending. 
 
The framework that was developed for measuring proven re-offending 
integrated these approaches into a single framework. This allowed users to: 
 
 form a clear picture of proven re-offending at national and local 
levels; 
 
 compare adult and youth results, and enable other work on transition 
between the youth and adult system; 
 
 understand how results for different offender groups (such as those 
managed by the prison and probation services, those under the PPO 
schemes, drug-misusing offenders, first time entrants, etc.) fit into the 
overall picture on proven re-offending; and 
 
 continue to analyse proven re-offending behaviour for particular types 
of offender. 
 

 
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Since its inception, the framework for measuring proven re-offending has 
undergone a number of changes as a result of changes to two key data 
streams. 
 
 Due to changes to the way drug testing data are collected centrally, 
from the quarterly report published 30 October 2014 (covering proven 
re-offending over the calendar year 2012) and for all later 
publications in the series, adults who test positive for Class A drugs 
alone (without receiving a conviction or caution) are no longer 
included. 
 
 Due to an inconsistency of the recording of the available data for 
PPOs, from the report published 29 January 2015 (covering proven 
re-offending over the period 1 April 2012 to 31 March 2013) and for 
all later publications in the series, results on this group are also no 
longer included. 
 
 Because of the aforementioned changes, all the offender 
characteristics needed to produce the predicted re-offending models 
used in publications prior to the April 2012 to March 2013 bulletin are 
no longer available. Therefore, from the report published 29 January 
2015 (covering proven re-offending over the period 1 April 2012 to 
31 March 2013) and for all later publications in the series, there is no 
longer any reference to a predicted rate. We are consulting on a 
replacement method for this, one option being version 4 of the 
Offender Group Reconviction Scale (OGRS4) score as used by the 
Transforming Rehabilitation (TR) programme as a predictor of re-
offending based on age, gender and criminal history. Further 
information on OGRS4 is available in Annex A. 
 
This bulletin is published alongside three inter-related bulletins: 
Offender Management Statistics Quarterly: provides key statistics 
relating to offenders who are in prison or under Probation Service 
supervision. 
 
Safety in Custody Statistics Quarterly, England and Wales: provides 
statistics on death, self harm and assault incidents whilst in prison custody. 
 
MAPPA (Multi Agency Public Protection Arrangements) Annual 
Report: this annual publication presents the number of MAPPA eligible 
offenders in England and Wales. 

 
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Measurement 
The underlying principle of measuring re-offending (or recidivism, which is 
the most commonly used term internationally) is that someone who has 
received some form of criminal justice sanction (such as a conviction or a 
caution) goes on to commit another offence within a set time period. 
 
Measuring true re-offending is difficult. Official records are taken from either 
the police or courts, but they will underestimate the true level of re-offending 
because only a proportion of crime is detected and sanctioned and not all 
crimes and sanctions are recorded on one central system. Other methods of 
measuring re-offending, such as self report studies, are likely to also 
underestimate the rate. 
 
Following the Ministry of Justice Consultation on Improvements to Ministry 
of Justice Statistics, a proven re-offence is defined as any offence 
committed in a one year follow-up period that resulted in a court conviction, 
caution, reprimand or warning in the one year follow-up or a further six 
month waiting period (to allow time for cases to progress through the 
courts). The data source is the extract of the Police National Computer 
(PNC) held by the Ministry of Justice. 
 
 
 
 
 

 
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Definitions for the measurement of proven re-offending 
Cohort 
This is the group of offenders for whom re-offending is measured. For the 
Proven Re-offending Statistics Quarterly Bulletin, this is defined as all 
offenders in any one year who received a caution, a final warning or 
reprimand (for juveniles), a non-custodial conviction or who were released 
from custody. 
 
Offenders who were released from custody or secure accommodation 
(juveniles only) or commenced a court order are matched to the PNC 
database. A proportion of cases are lost in this process because they 
cannot be matched (see the section below titled “Matching offender records” 
for further details). Additionally, offenders who appear multiple times in the 
cohort are only included once (see the section below titled “Multiple offender 
entries” for further details). 
 
The group of offenders whose offending behaviour is proven is likely to be a 
sub-group of all active offenders. The Offending, Crime and Justice Survey 
(2003)1 estimated that around one in ten people in England and Wales aged 
between ten and 65 had committed an offence in the previous 12 months, 
which translates into approximately 3.8 million people. This compares to 
around 632,000 offenders in the 2002 cohort used to measure proven re-
offending, underlining that the offenders whose proven re-offending 
behaviour is presented in the Proven Re-offending Statistics Quarterly 
Bulletin are a small and probably unrepresentative sample of the population 
of all active offenders. 
 
Index disposal (sentence type) 
The index disposal of the offender is the type of sentence the offender 
received for their index offence. For the Proven Re-offending Statistics 
Quarterly Bulletin, this is defined as custody, court order, other disposal 
resulting from a conviction at court, such as a fine or discharge, caution, 
reprimand or final warning (young offenders). 
 
Index offence 
The index offence is the proven offence that leads to an offender being 
included in the cohort. An offence is only counted as an index offence if it is: 
 
 recordable (see below); 
 
 committed in England and Wales; 
 
 prosecuted by the police; and 
                                            
1 The Offending, Crime and Justice Survey (2003) was a random probability survey of 
10,079 people aged from ten to 65 and asked people about their offending history. Like any 
such survey, its accuracy is dependent upon the level of honesty with which respondents 
completed the survey. 

 
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 not a breach offence. 
 
Start point (index date) 
This is the set point in time from when proven re-offences are measured. 
For the Proven Re-offending Statistics Quarterly Bulletin, this is defined as 
the date of prison discharge, the date of court conviction for non-custodial 
sentences, or the date of receipt for a caution, reprimand or final warning. 
 
Follow-up period 
This is the length of time over which proven re-offending is measured. For 
the Proven Re-offending Statistics Quarterly Bulletin, this is defined as 12 
months from the start point. 
 
Waiting period 
This is the additional time beyond the follow-up period to allow for offences 
which are committed towards the end of the follow-up period to be proven 
by a court, resulting in a conviction, caution, reprimand or final warning. For 
the Proven Re-offending Statistics Quarterly Bulletin, this is six months. 
 
Figure 1 below illustrates why different offences for an example offender are 
included or excluded in the proven re-offending measure. 
 
Figure 1: How events of re-offending are included in the measure? 
Event G
1 Offence 
Committed
Event A
2 Offences 
Committed
Conviction 1 
for Event A
Caution 1 for 
Event B
Event B
1 Offence 
Committed
Conviction 2 
for Events C & 
D
Event C
3 Offences 
Committed
Event D
1 Offence 
Committed
Event E
1 Offence 
Committed
Conviction 4 
for Event E
Within the one-year 
follow up period
6-month waiting 
period
Event F
2 Offences 
Committed
Conviction 3 
for Event F
Conviction 5 
for Event G
After waiting period
 
 
Events A to E all occur in the one year follow-up period, but events F and G 
are outside this period, so would not be counted. Events A to D are all 
counted because they were all proven within the one year follow-up period 
or the further six month waiting period, but event E, even though the offence 
took place in the one year follow-up period, would not be counted, as the 
conviction did not occur within either the one year follow-up period, or the 
further six month waiting period. The offender has, therefore, committed 
seven proven offences during the one year follow-up period (two for event 
A, one for event B, three for event C, and one for event D). 
 
Proven re-offence 
Offences are counted as proven re-offences if they meet all of the following 
criteria: 
 
 They are recordable. Not all offences are on the PNC and more 
recordable offences are entered than non-recordable offences. 
Analysis comparing offences proven at court with offences recorded 
on the PNC suggests the most cost common offences that are not 

 
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recorded relates to motor vehicles, e.g. using a motor vehicle whilst 
uninsured against third party risks, speeding offences, keeping a 
vehicle on the highway without a driving licence or television licence 
evasion. 
 
 They were committed in England or Wales. 
 
 They are offences that were prosecuted by the police. PNC data are 
collected and input by the police and offences prosecuted by the 
police are likely to be recorded more comprehensively on the PNC 
than offences that are prosecuted by other organisations. For 
example, benefit fraud is prosecuted by the Department for Work and 
Pensions. Therefore, benefit fraud offences may be poorly 
represented on the PNC. 
 
 Offences are only counted if they are proven through caution, 
reprimands or final warnings (for juveniles) and court convictions. 
Offences that are not proven, or which meet with other responses 
from the Criminal Justice System, are not counted. The Offending, 
Crime and Justice Survey (2003) estimated that 6% of all offences 
resulted in any contact with the Criminal Justice System. 
 The offence is not a breach offence, i.e. breach of a court order, 
since we are only interested in new offences. 
 
Measures of proven re-offending 
Proven re-offending data are presented in the following ways: 
 
 The number of offenders. 
 
 The proportion of offenders who are proven re-offenders. 
 
 The average number of proven re-offences among re-offenders. 
 
 The average number of proven re-offences among all offenders 
including those who committed no proven re-offences (previously the 
frequency rate). 
 
 The proportion of proven offenders who committed a proven serious 
violent or sexual re-offence against the person. Refer to Annex A for 
details on what counts as a serious violent or sexual offence. 
 
 The proportion of proven offenders who committed a proven serious 
acquisitive re-offence. Refer to Annex A for details on what counts as 
a serious acquisitive offence. 
 
Multiple offender entries 
Each offender is tracked over a fixed period of time and any proven offence 
committed in this period is counted as a proven re-offence. A multiple 
offender entry refers to an offender who, after entering the cohort in a given 
year, commits a re-offence and is either cautioned, discharged from prison 

 
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or gets a non-custodial conviction in the same cohort year. This re-offence 
could also be included as a second entry for this offender into the cohort. 
 
Figure 2: Example of an offender with multiple offender entries 
 
 
 
 
 
 
To date, publications have avoided the double counting of these multiple 
offender entries (MOE) by only counting an individual once based on their 
first proven offence in the relevant time period. In the illustration above, the 
caution would be counted as the index disposal and the further two proven 
offences would be counted as re-offences. This avoids double counting of 
proven re-offences. 
 
In this publication the main tables (tables A1 to A6 and B1 to B4) in the 
report have been produced on the basis of the 'first proven offence in the 
relevant time period’ which led to an offender being included. This provides 
a picture of proven re-offending which is consistent with previous 
publications and tracks an offender, irrespective of the disposal they 
receive, to when they commit a proven re-offence. 
 
The measure of proven re-offending now covers all offenders in any one 
year instead of the first quarter of a calendar year as in previous proven re-
offending publications. The result is many more offenders with multiple 
entries. 
 
In addition, including cautions to identify a proven offence means many 
offenders’ first offence will be associated with a caution since cautions 
account for around a third of adult offenders in one year. Table 1 shows the 
number of offenders in each cohort period by their number of entries. 
 
Table 1: Number of offenders and their respective number of entries for 
2000, 2002 to 2012 cohorts1 
 
Multiple
Offender Entries
2000
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
1
512,551
522,376
544,031
549,545
580,709
615,775
630,748
602,251
572,068
528,466
498,364
459,250
2x
75,311
77,813
81,651
78,827
80,968
86,866
90,870
87,427
83,235
78,430
74,314
66,028
3x
19,565
21,208
22,073
20,840
20,908
21,823
23,590
23,499
22,005
21,332
20,479
17,892
4x
6,195
6,689
7,074
6,833
6,720
6,768
7,605
7,882
7,319
7,396
7,115
6,289
5x
1,998
2,314
2,392
2,355
2,355
2,411
2,774
2,894
2,927
2,902
2,963
2,592
6 to 10x
1,240
1,510
1,689
1,641
1,505
1,509
1,964
2,332
2,303
2,361
2,500
2,292
Greater than 10x
164
155
129
131
119
115
114
160
202
193
190
178
Total MOEs
104,473
109,689
115,008
110,627
112,575
119,492
126,917
124,194
117,991
112,614
107,561
95,271
% of total cohort
16.9%
17.4%
17.5%
16.8%
16.2%
16.3%
16.8%
17.1%
17.1%
17.6%
17.8%
17.2%
Cohort
617,024
632,065
659,039
660,172
693,284
735,267
757,665
726,445
690,059
641,080
605,925
554,521 
 
1. Data are not available for 2001 due to a problem with archived data on Court Orders. 
 
The number of offenders with multiple entries has remained fairly constant 
over time - the proportion of the total that had multiple offender entries has 
remained at about 16 to 18% between 2000 and 2012. 
Offender 
Cautioned
Re-offence 1 
Offender starts a 
community 
sentence 
Re-offence 2 
Offender 
sentenced to 
3mnths in prison 
then released 
Re-offence 3 
1 year cohort period
Offender 
Cautioned
Offender 
Cautioned
Re-offence 1 
Offender starts a 
community 
sentence 
Re-offence 2 
Offender 
sentenced to 
3mnths in prison 
then released 
Offender 
sentenced to 
3mnths in prison 
then released 
Re-offence 3 
1 year cohort period

 
 
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Proven re-offending by index disposal, probation trust and prison 
In order to measure proven re-offending on a consistent and representative 
basis by offender management groups, it is necessary to distinguish 
between the disposal (sentence) types that led to an offender being 
included. Doing this allows the cohort to be defined according to the relative 
start point of an offender’s interaction with the prison (released from 
custody) or probation services (court order commencement). 
 
Tables C1-C3 provide re-offending data by disposal (sentence) types. 
These are produced on the basis of an individual’s first disposal (sentence) 
in that category. In the illustration above, the individual would appear once 
in the caution category, once in the community order category and once in 
the custody category. These tables will include an overall prison and 
probation proven re-offending rate which will be the figures we quote 
publicly. However, these figures should not be used when comparing 
proven re-offending rates across different disposals to compare 
effectiveness. Instead the Compendium of Re-offending Statistics and 
Analysis 2013 publication should be referred to as this analysis controls for 
offender characteristics in order to give a more reliable estimate of the 
relative effectiveness of different disposals. 
 
 
The prison/youth secure accommodation/probation trust data tool provide 
re-offending rates by individual prison and former probation trust, and 
National Probation Service Division (NPS). These are produced on the 
basis of an individual’s first disposal from each specified prison or probation 
trust. If the individual offender is discharged from two different prisons in the 
year they will appear in both of the prison’s re-offending rates. The same 
applies for offenders commencing court orders in more than one probation 
trust within the year. This is to allow prisons and probation services to track 
their caseload of offenders. 

 
 
11
Early estimates of proven re-offending statistics 
Background 
Responses from the consultation and from earlier engagement with 
representatives of front-line offender management services supported the 
proposal to produce early estimates of proven re-offending using shorter 
follow-up and waiting periods. This is intended to provide offender 
managers feedback on the proven re-offending trends of offenders they are 
working with in time for them to adjust or build on offender management 
operational policy. This section of the bulletin addresses these issues. 
 
Early estimates of proven re-offending were previously presented for four 
particular offender groups; those managed by the probation service, prolific 
and other priority offenders (PPOs), drug-misusing offenders and young 
offenders managed by youth offending teams. Owing to changes described 
earlier data are now only presented for young offenders who are managed 
by youth offending teams (YOTs). 
 
Proven re-offending for the early estimates is measured in exactly the same 
way as for the headline proven re-offending measure except that the follow-
up period and waiting period are both three months each. (For the headline 
measure of proven re-offending they are 12 months and six months, 
respectively.) 
 
The headline figures and early estimates differ in the following ways: 
 
 Early estimates of proven re-offending rates are considerably lower 
than in the headline publication. This is because they cover a shorter 
time period. 
 The shorter follow-up period and waiting period allow rates to be 
calculated for more recent groups of proven offenders. 
 Early estimates of proven re-offending rates provide local offender 
management services with information on proven re-offending trends 
for the offenders they are working with. The headline re-offending 
publication presents the public with information on a wide range of 
proven re-offending trends and provides proven re-offending rates by 
a variety of breakdowns, such as age, gender, disposal (sentence 
type), etc. 
 The shorter follow-up period and waiting period provides insufficient 
time for many serious re-offences to be committed and convicted. For 
this reason, early estimates of proven re-offending rates do not 
include information on serious re-offending. 

 
 
12
Local adult re-offending statistics quarterly 
bulletin 
Background 
The Local Adult Re-offending Statistics Quarterly Bulletin series was 
published by the Ministry of Justice from February 2009 to May 2014 at 
Government Office Region, probation trust and local authority level. This 
data was used to measure probation performance.  
 
The local proven re-offending data measured the re-offending of all 
offenders on the probation caseload. This included offenders that were on 
licence and those that were serving court orders. 
 
Local proven re-offending rates used the same follow-up period and waiting 
period to those for the early estimates. However, there were several key 
differences between the local measure and the early estimates. These 
included: 
 
 The sample of offenders - local rates were estimated using all 
offenders on the probation caseload, which included those on licence 
and those that were serving court orders. Offenders on the caseload 
were identified through four ‘snapshots’ of the caseload, which were 
taken each quarter. Offenders were included if they were on the 
caseload even if they had been on licence or had been serving the 
court order for longer than 12 months. The early estimates are based 
on offenders who commence a court order within a 12 month period. 
 Local rates defined the period reported on by the period of re-
offending. The early estimates refer to the year of the index disposal. 

 
 
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Data quality 
The data required for measuring proven re-offending are based on a range 
of data sources (prison data, probation data, young offenders in secure 
accommodation, and criminal records from the Police National Computer) 
from a range of agencies (the National Offender Management Service, the 
Youth Justice Board, local authorities and the National Police Improvement 
Agency). These figures 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. 
 
 
Police National Computer data 
 
Information regarding the proven re-offending behaviour of offenders has 
been compiled using the Ministry of Justice’s extract from the Police 
National Computer (PNC). The process involves matching offender details 
from the prison and probation data to the personal details recorded on the 
PNC. A proportion of cases cannot be matched and the figures presented in 
Table 2 below are expressed as a percentage of the offenders that are 
matched. Like any large scale recording system, the PNC is subject to 
errors with data entry and recording. The PNC is regularly updated so that 
further analysis at a later date will generate revised figures. 
 
The quality of the information recorded on the PNC is generally assumed to 
be relatively high as it is an operational system on which the police depend, 
but analysis can reveal errors that are typical when handling administrative 
datasets of this scale. The extent of error or omitted records on the PNC is 
difficult to estimate because it is a unique data source. As a result, there is 
not always an obvious source of data to provide a baseline from which to 
assess data quality. For some types of results, however, comparisons can 
be made. For example, the trend in receptions into prison in each month is 
very similar using the PNC and prisons data (see below for details). 
Although the number of receptions recorded on the PNC is consistently 
slightly lower because prisons data include cases on remand whereas the 
PNC does not. Another example is the number of cases that are given a 
custodial sentence, broken down by offence type, which is similar using the 
PNC and the Court Proceedings Database with a match rate of 97%. 
 
A number of improvements are routinely carried out: 
 
 Updates to the coding and classification of offences and court 
disposals, including the reduction of uncoded offences, the reduction 
in the use of miscellaneous offence codes and the clarification of the 
coding of breach offences; 
 Updates to the methods used to identify the primary offence, where 
several offences are dealt with on the same occasion, and the 
methods used to identify the primary disposal, where an offence 
attracts more than one court disposal; and 

 
 
14
 Removal of some duplication of records within the database resulting 
in improvements to the efficiency and reliability of the matching 
process. 
 
 
Prison data 
 
Prison establishments record details for individual inmates on the prison IT 
system (Prison-NOMIS or LIDS). The information recorded includes details 
such as date of birth, gender, religion, nationality, ethnic origin, custody 
type, offence, reception and discharge dates and, for sentenced prisoners, 
sentence length. The data from individual prison establishments then feeds 
through to a central computer database, called the Inmate Information 
System (IIS). 
 
In May 2009, the National Offender Management Service (NOMS) began 
the roll-out of a new case management system for prisons (Prison-NOMIS). 
During the phased roll-out, data collection issues emerged that affected the 
supply of data for statistical purposes from July 2009 to February 2010. 
Specifically, statistical information on sentence length and offence group is 
not available on any of our prison datasets for this period. 
 
In order to ensure the fullest possible set of data from July 2009 to February 
2010, sentence lengths were estimated for those prisoners received or 
discharged before the problems were resolved. At the point when the 
problems were resolved, a small number of prison establishments were still 
using the old LIDS case management system; data for prisoners received or 
discharged from these prisons was assumed to be unaffected. 
 
For those prisoners received or discharged from prisons operating Prison-
NOMIS, efforts were made to populate their record with the correct 
sentence length using other data extracts. For example, many prisoners 
discharged in January 2010 were originally received into prison prior to July 
2009, so their sentence length was taken from unaffected datasets before 
the problems began. Similarly, the majority of those received in early 2010 
were still in prison in March 2010 when the problems were resolved, so the 
sentence length from the corrected prison population data was used. 
 
Where it was not possible to populate a sentence length using other 
datasets, prisoners were allocated a sentence length band based on the 
number of days they spent in custody (taking account of early release 
schemes where relevant). 
 
As a check on the methodology, an alternative estimation process was 
designed and the number of discharges in each sentence length band for 
the second half of 2009 was compared using the two methods. 
 
A number of estimation methods were considered and tested on the 2008 
data (prior to the data problems) to see which yielded estimates closest to 
the actual 2008 data. This identified the following method: 
 

 
 
15
1. Calculate data for the first half of the year as a proportion of the full 
calendar year, for each year from 2001 to 2008; separately for each 
sentence length band or offence group (the two key breakdowns to 
be estimated). 
 
2. Apply the average of these proportions to the January to June 2009 
data to estimate the 2009 annual totals; separately for each sentence 
length band or offence group. 
 
3. Scale the estimated numbers in each sentence length band or 
offence group to sum to the annual total recorded in the raw data 
(where the totals are known to be correct). 
 
The maximum difference between the two approaches was 2.6% in the 
band ‘12 months to less than 4 years’; for all other bands the difference was 
less than 1%. 
 
Indeterminate sentence prisoners 
In addition to the above, data on the discharge of prisoners on 
indeterminate sentences, i.e. prisoners given a life sentence or an 
Indeterminate sentence for Public Protection (IPP), is provided from the 
Public Protection Unit Database (PPUD). This holds data jointly owned by 
the Offender Management and Public Protection Group (OMPPG) in NOMS 
and the Parole Board. 
 
PPUD records details of all indeterminate sentence prisoners at the point of 
conviction, those engaged in the Generic Parole Process and prisoners 
(determinate and indeterminate) who have been recalled from licence. It 
also covers those who have received a restricted hospital order/direction 
from a Crown Court, and those remand and convicted prisoners who have 
been transferred from prison/detention centres to psychiatric hospital under 
the relevant sections of mental health legislation. 
 
All decisions taken by the NOMS casework sections and the Parole Board 
are recorded on the system. 
 
Personal information recorded includes (but is not limited to) name, date of 
birth, gender, identifying numbers, ethnicity, last known address, probation 
area and sentencing information. 
 
OMPPG and the Parole Board run monthly and ad hoc reports to cleanse 
data that are not otherwise identified by data validation routines built into the 
system. 

 
 
16
Probation data 
 
Since 2005, detailed information on the supervision of offenders (at the 
individual offender level) had been submitted by probation trusts on a 
monthly basis. These monthly ‘probation listings’ included information on 
offenders starting probation supervision. Between 2002 and 2005, this 
information was submitted quarterly, and prior to 2002 a different data 
collection system was in place, which meant that information on caseload 
had to be calculated based on the number of people starting supervision 
and the number of terminations. From June 2014, the Transforming 
Rehabilitation programme was launched, which changed the way offenders 
are managed in the community. Management of offenders serving their 
sentence in the community has been split into two groups, one consisting of 
high risk offenders who are managed by the National Probation Service 
(NPS) and another group consisting of low to medium risk offenders who 
are now managed by Community Rehabilitation Companies (CRCs). 
 
The quality of the information recorded on the probation data is generally 
assumed to be relatively high as it is a direct extract from an operational 
system upon which the probation service depends for managing offenders 
locally. The extract consists of a small number of key fields for which 
completion is mandatory. Data is received centrally via the nDelius case 
management system and is subject to another set of data validation 
processes. Trends from the data are consistent with comparable time series 
from the Courts Proceeding Database. Any large scale recording systems 
are subject to possible errors with data entry and processing, but there are 
no known issues regarding the probation commencements data. 
 
 
Young offenders in secure accommodation 
 
Information about secure training centres (STCs) and secure children’s 
homes (SCHs) comes from the Youth Justice Board's (YJB) eAsset 
database. Information about young people aged 17 and under and held in 
YOIs is supplied by the Prison Service and private YOIs. 
 
The YJB monthly custody report has traditionally used data from the Secure 
Accommodation Clearing House System (SACHS), this was the system 
used by the YJB to book young people into custody. To meet information 
management challenges of a growing department and whilst improving our 
processes, the YJB has migrated to the use of the new eAsset system since 
March 2012. 
 
As part of the work to implement the new system both SACHS and eAsset 
were run in parallel from 5th March to 1st July 2012. The YJB now has the 
ability to produce some reports from eAsset and has done work to quality 
assure the outputs against SACHS. While this work is ongoing and further 
reports are being developed we now believe the quality of data from this 
system is of a suitable level to publish as management information. 
 
The quality of the information recorded on the eAsset database is generally 
assumed to be relatively high as it is a direct extract from an operational 

 
 
17
system which is used to place young people in custody. The extract uses a 
number of key fields for which completion is mandatory when booking a 
young person into custody. 
 
 
Data processing and analysis 
 
The data underpinning the results are considered by Ministry of Justice to 
be broadly robust. Considerable work has been carried out ensuring data 
quality, and the data have been used for research publications. Scrutiny of 
the data source continues in order to ensure the data remains reliable. 
 
The National Audit Office (NAO) identified risk factors in its review of the 
reporting of PSA targets (NAO, 2005). The remainder of this section 
addresses these. 
 
 
Matching offender records 
 
This process involves matching data on prison discharges and court order 
commencements to the PNC database. The process uses automated 
matching routines that look at offenders’ surnames, initials, and dates of 
birth, using direct name matching along with a variety of ‘sounds like’ 
algorithms. The matching algorithm also searches through PNC held 
information on alias names and dates of birth for offenders. However, not all 
offenders are matched and a thorough analysis of bias in the matching 
system has yet to be undertaken. Table 2 below shows that the overall 
matching rates between 2000 and 2012 have remained high. 

 
 
18
Table 2: Matching rates for the different data sources for 2000, 2002 to 
2012 cohorts1 
 
2000
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
Prison
Prison discharges
87,083
87,338
85,920
86,970
84,897
83,725
87,340
95,824
94,114
93,137
89,773
91,009
Automatically matched to the PNC
80,572
81,211
80,121
81,125
79,398
78,285
81,874
90,021
88,745
87,845
84,950
86,333
Matched to an index date
73,810
75,121
73,327
73,390
71,246
68,185
69,741
76,668
74,189
65,278
67,512
71,059
Percentage matched to the PNC
92.5%
93.0%
93.3%
93.3%
93.5%
93.5%
93.7%
93.9%
94.3%
94.3%
94.6%
94.9%
Percentage matched to the PNC and index 
offences (not breach etc.)
84.8%
86.0%
85.3%
84.4%
83.9%
81.4%
79.9%
80.0%
78.8%
70.1%
75.2%
78.1%
Court Orders
Court order starts
136,023
154,621
158,750
164,831
163,681
176,346
187,386
189,643
191,784
186,417
179,206
165,959
Automatically matched to the PNC
123,540
142,838
148,257
154,075
158,416
172,906
184,740
187,253
190,128
185,112
178,026
164,937
Matched to an index date
105,685
115,108
119,446
122,927
130,307
148,072
159,279
163,519
167,378
164,579
159,533
147,681
Percentage matched to the PNC
90.8%
92.4%
93.4%
93.5%
96.8%
98.0%
98.6%
98.7%
99.1%
99.3%
99.3%
99.4%
Percentage matched to the PNC and index 
offences (not breach etc.)
77.7%
74.4%
75.2%
74.6%
79.6%
84.0%
85.0%
86.2%
87.3%
88.3%
89.0%
89.0%
YJB2
YJB discharges
-
1,337
1,612
1,521
1,551
1,564
1,553
1,647
1,626
1,770
891
836
Automatically matched to the PNC
-
1,226
1,502
1,425
1,448
1,464
1,463
1,537
1,564
1,682
852
801
Matched to an index date
-
680
818
785
800
769
780
845
817
916
647
607
Percentage matched to the PNC
-
91.7%
93.2%
93.7%
93.4%
93.6%
94.2%
93.3%
96.2%
95.0%
95.6%
95.8%
Percentage matched to the PNC and index 
offences (not breach etc.)
-
50.9%
50.7%
51.6%
51.6%
49.2%
50.2%
51.3%
50.2%
51.8%
72.6%
72.6% 
 
1. Data are not available for 2001 due to a problem with archived data on Court Orders. 
2. A new data collection method began in March 2012. 
 
The total number of offenders matched to the PNC is substantially higher 
than the final figure for the cohorts – for example, in 2012 there were 
252,071 matched offenders, but a final cohort size of 219,347. The main 
reasons for these discrepancies are: 
 
 Conviction dates for the beginning of the community, suspended or 
custodial sentence do not match the conviction date within seven 
days of the criminal records from the PNC database; 
 The index offence was not dealt with by a Home Office police force – 
this ensures that only offences in England and Wales are counted; 
 Exclusion of all offenders where the index offence is a breach, since 
we are only interested in new offences; and 
 Exclusion of multiple offender entries (see section above titled 
“Multiple offender entries” for further details). 
 
 
Counting rules 
 
The counting rules for choosing which prison discharges to include offer a 
variety of choices. For instance, it makes little sense to include offenders 
deported on release or who have died. These counting rules were 
enumerated and discussed to ensure a more accurate and consistent count 
and are reviewed on an annual basis to ensure a consistent approach. 

 
 
19
Complexity of data processing and analysis 
 
The data processing involved for measuring re-offending is complex. To 
analyse re-offending behaviour by previous offending or disposal history 
requires the extraction of criminal histories that can span a number of 
decades, and the subsequent matching of these histories against the 
probation caseload files and prison discharges in order to generate a 
dataset. 
 
 
The extraction of the criminal histories 
 
To quality assure the extraction of criminal histories, a small set of random 
samples of offenders was taken after the analysis to check, via a basic 
validation, that outputs of the SQL (Structured Query Language) program 
were accurate. The Ministry of Justice is confident that this process has 
been successful. 
 
 
Level of subjectivity 
 
There is relatively little subjectivity in the system. Occasional judgements 
are required (e.g. where to classify an offence), but these will not 
significantly influence the results. 
 
 
Maturity and stability of the data system 
 
The system is well established having been used a number of times to 
produce re-offending statistics for publication. Nonetheless, vigilance 
continues to be exercised to ensure the validity of the results. 
 
 
Expertise of those who operate the system 
 
Prison and court order data-feeds are continually monitored and 
improvement work is regularly undertaken to improve the reliability and the 
accuracy of datasets. The internal processing of the results within the 
Ministry of Justice has been subject to dip sampling of criminal histories and 
the statistical model has been extensively tested. 
 
 
Interpreting trends in the proportion of offenders who 
commit a serious re-offence against the person 
 
Care should be taken when interpreting the severity rate for the following 
reasons: 
 
 Time through the Criminal Justice System – more serious 
offences are likely to take a longer time to progress through the 
Criminal Justice System than less serious offences. The proven re-

 
 
20
offending statistics track proven re-offending behaviour for a year 
upon offenders entering the cohort, plus an additional six months for 
convictions to be updated on the system. There is a risk that this time 
scale is not long enough to capture the most serious offences. 
However, analysis suggests that the number of serious proven re-
offences picked up by the measure remains comparatively stable 
year on year, ensuring performance is comparable over time. 
 Reporting variation – variation in reporting time between police 
force areas and courts may also have an impact on how many 
serious offences are captured during the one year follow-up period. 
 
 
Data on historical trends 
 
The data used to measure proven re-offending is from the PNC. Police 
forces started to enter criminal records locally in 1995. In order to allow time 
for good practice among police forces in entering data onto the PNC to 
become embedded, PNC data was used to measure proven re-offending for 
the first time in 2000. Prior to the 2012, headline bulletin results were 
compared to 2000 to highlight long-term trends. From 2012, results are 
compared to 2002, and in the future the year of comparison will move 
forward by one year for each calendar year publication. Results prior to 
2000 cannot be compared to results from 2000 onwards for two main 
reasons: 
 
 Change in data source – re-offences are measured using data from 
the PNC (which covers recordable offences), whereas data from 
years before 2000 were measured using the offenders index (which 
covered a narrower range of offences). 
 Change in measurement – the concept being measured from 2000 
onwards in these reports is that of using the offence date to measure 
re-offences (a period of time is allowed for offences to be committed, 
and a further period allowed for these offences to be proved by 
caution, reprimand, final warning or court conviction), whereas the 
concept being measured prior to 2000 was that of using the 
conviction date to measure re-convictions (any conviction occurring 
in a set period of time, whether or not the offence occurred in that 
time period). 
 
However, the Compendium of Re-offending Statistics and Analysis 2010, 
published in November 2010, provides the most consistent statistical series 
possible between 1971 and 2006, adjusting for known methodological 
changes. For more information, please refer to Chapter 4.4 at the following 
link. 
 
 
Results for 2001 cannot be calculated for offenders on court orders because 
of a problem with archived data on court orders. 

 
 
21
Local breakdowns of the headline proven re-offending rates are available 
from 2005 onwards. Proven re-offending data are broken down by locality 
using the address and post-code information of the offender. Where this 
information is missing, the location of the processing police force is used 
instead. This is not a completely reliable indicator of the offender’s home 
address as offenders may offend in a different locality than where they 
reside. The completeness of this information has improved over time. In 
2000, this information was omitted for 29% of cases, which was considered 
too high to produce reliable results. By 2005, this was reduced to 16.5%, 
and there has been a continuing downward trend since then. 

 
 
22
Statistical modelling and coefficients 
Introduction 
Owing to the removal of variables which relate to drug misusing offenders 
and Prolific and other Priority Offenders (PPOs), there are no longer the 
offender characteristics needed to produce the statistical model which 
previously calculated the predicted rate. Therefore, there is no predicted 
rate available for all cohorts after the one published 30 October 2014 
(covering re-offending for the calendar year 2012). We are consulting on a 
replacement method for this, one option being version 4 of the Offender 
Group Reconviction Scale (OGRS4) score as used by the Transforming 
Rehabilitation (TR) programme as a predictor of re-offending based on age, 
gender and criminal history. 

 
 
23
Appendix A: List of serious offences 
Serious violence against the person 
1.  Murder: 
1. 
Of persons aged 1 year or over. 
2. 
Of infants under 1 year of age. 
 
2. 
Attempted murder. 
 
4. 
Manslaughter, etc: 
1. 
Manslaughter. 
2. 
Infanticide. 
3. 
Child destruction. 
 
 
   
 
 
 
5. 
Wounding or other act endangering life: 
1. 
Wounding, etc. with intent to do grievous bodily harm, etc. or to resist 
apprehension. 
2. 
Shooting at naval or revenue vessels. 
4. 
Attempting to choke, suffocate, etc. with intent to commit an indictable offence 
(garrotting). 
5. 
Using chloroform, etc. to commit or assist in committing an indictable offence. 
6. 
Burning, maiming, etc. by explosion. 
7. 
Causing explosions or casting corrosive fluids with intent to do grievous bodily 
harm. 
8. 
Impeding the saving of life from shipwreck. 
9. 
Placing, etc. explosives in or near ships or buildings with intent to do bodily 
harm, etc. 
10. Endangering life or causing harm by administering poison. 
11. Causing danger by causing anything to be on road, interfering with a vehicle or 
traffic equipment. 
13. Possession, etc. of explosives with intent to endanger life. 
14. Possession of firearms, etc. with intent to endanger life or injure property, etc. 
(Group I). 
15. Possession of firearms, etc. with intent to endanger life or injure property, etc. 
(Group II). 
16. Possession of firearms, etc. with intent to endanger life or injure property, etc. 
(Group III). 
17. Using, etc. firearms or imitation firearms with intent to resist arrest, etc. (Group 
I). 
18. Using, etc. firearms or imitation firearms with intent to resist arrest, etc. (Group 
II). 
19. Using, etc. firearms or imitation firearms with intent to resist arrest, etc. (Group 
III). 
 
[Group I - Firearms, etc. other than as described in Group II or III. 
 
Group II - Shotguns as defined in s.1 (3)(a) of the Firearms Act 1968. 
 
Group III - Air weapons as defined in s.1 (3)(b) of the Firearms Act 1968] 
20. Use etc. of chemical weapons. 
21. Use of premises or equipment for producing chemical weapons. 
22. Use, threat to use, production or possession of a nuclear weapon. 
23. Weapons related acts overseas. 
24. Use of noxious substances or things to cause harm or intimidate. 
25. Performing an aviation function or ancillary function when ability to carry out 
function is impaired because of drink or drugs. 
26. Endangering safety at sea/aerodromes. 
27. Torture. 
 
8. 
Other wounding, etc.: 
1. 
Wounding or inflicting grievous bodily harm (inflicting bodily injury with or without 
weapon).  

 
 
24
33. Racially aggravated wounding or inflicting grievous bodily harm (inflicting bodily 
injury with or without weapon). 
40. Religiously aggravated malicious wounding or GBH. 
46. Racially or religiously aggravated malicious wounding or grievous bodily harm. 
 
Sexual offences 
17. Sexual assault on a male (previously indecent assault on a male): 
11. Indecent assault on male person under 16 years. 
12. Indecent assault on male person 16 years or over. 
13. Assault on a male by penetration. 
14. Assault of a male child under 13 by penetration. 
15. Sexual assault on a male. 
16. Sexual assault of a male child under 13. 
 
19. Rape: 
2. 
Man having unlawful sexual intercourse with a woman who is a defective. 
3. 
Male member of staff of hospital or mental nursing home having unlawful sexual 
intercourse with female patient. 
4. 
Man having unlawful sexual intercourse with mentally disordered female patient 
who is subject to his care. 
7. 
Rape of a female aged under 16. 
8. 
Rape of a female aged 16 or over. 
9. 
Rape of a male aged under 16. 
10. Rape of a male aged 16 or over. 
11. Attempted rape of a female aged under 16. 
12. Attempted rape of a female aged 16 or over. 
13. Attempted rape of a male aged under 16. 
14. Attempted rape of a male aged 16 or over. 
16. Rape of female child under 13 by a male. 
17. Rape of a male child under 13 by a male. 
18. Attempted rape of a female child under 13 by a male. 
19. Attempted rape of a male child under 13 by a male  
 
20. Sexual assault on female (previously indecent assault on a female): 
1. 
On females under 16 years of age. 
2. 
On females aged 16 years and over. 
3. 
Assault on a female by penetration. 
4. 
Assault on a female child under 13 by penetration. 
5. 
Sexual assault on a female. 
6. 
Sexual assault on a female child under 13. 
 
21. Sexual activity (male and female) (including with a child under 13) (previously unlawful 
intercourse with a girl under 13): 
2. 
Causing or inciting a female child under 13 to engage in sexual activity - 
penetration. 
3. 
Causing or inciting a female child under 13 to engage in sexual activity - no 
penetration. 
4. 
Causing or inciting a male child under 13 to engage in sexual activity - 
penetration 
5. 
Causing or inciting a male child under 13 to engage in sexual activity - no 
penetration. 
6. 
Sexual activity with a female child under 13 - offender aged 18 or over - 
penetration. 
7. 
Sexual activity with a male child under 13 - offender aged 18 or over - 
penetration. 
8. 
Causing or inciting a female child under 13 to engage in sexual activity - 
offender aged 18 or over – penetration. 
9. 
Causing or inciting a male child under 13 to engage in sexual activity - offender 
aged 18 or over - penetration. 
10. Engaging in sexual activity in the presence of a child under 13 (offender aged 
18 or over). 

 
 
25
11. Causing a child under 13 to watch a sexual act (offender aged 18 or over). 
12.   Sexual activity with a female child under 13 - offender aged under 18. 
13.   Sexual activity with a male child under 13 - offender aged under 18. 
14.   Causing of inciting a female child under 13 to engage in sexual activity - 
offender under 18. 
15. Causing or inciting a male child under 13 to engage in sexual activity - offender 
under 18. 
16. Engaging in sexual activity in the presence of a child under 13 - offender under 
18. 
17. Causing a child under 13 to watch a sexual act - offender under 18. 
18. Sexual activity with a female under 13 - offender aged 18 or over - no 
penetration. 
19. Sexual activity with a male child under 13 - offender aged 18 or over - no 
penetration. 
20. Causing or inciting a female child under 13 to engage in sexual activity - 
offender aged 18 or over - no penetration. 
21. Causing or inciting a male child under 13 to engage in sexual activity - offender 
aged 18 or over - no penetration. 
22. Sexual activity with a female child under 13 - offender aged under 18 - no 
penetration. 
23. Sexual activity with a male child under 13 - offender aged under 18 - no 
penetration. 
24. Causing or inciting a female child under 13 to engage in sexual activity - 
offender aged under 18 - no penetration. 
25. Causing or inciting a male child under 13 to engage in sexual activity - offender 
aged under 18 - no penetration. 
 
 22. Sexual activity (male and female) (including with a child under 16) (previously unlawful 
sexual intercourse with a girl under 16): 
0. 
Unlawful sexual intercourse with girl under 16 (offences committed prior to 1 
May 2004). 
2. 
Causing a female person to engage in sexual activity without consent – 
penetration. 
3. 
Causing a male person to engage in sexual activity without consent – 
penetration. 
4. 
Causing a female person to engage in sexual activity without consent - no 
penetration. 
5. 
Causing a male person to engage in sexual activity without consent - no 
penetration. 
6. 
Sexual activity with a female child under 16 (offender aged 18 or over) – 
penetration. 
7. 
Sexual activity with a male child under 16 (offender aged 18 or over) – 
penetration. 
8. 
Causing or inciting a female child under 16 to engage in sexual activity (offender 
aged 18 or over) - penetration 
9. 
Causing of inciting a male child under 16 to engage in sexual activity (offender 
aged 18 or over) – penetration. 
10. Engaging in sexual activity in the presence of a child under 16 (offender aged 
18 or over). 
11. Causing a child under 16 to watch a sexual act (offender aged 18 or over). 
18. Sexual activity with a female child under 16 - offender aged 18 or over - no 
penetration. 
19. Sexual activity with a male child under 16 - offender aged 18 or over - no 
penetration. 
20. Causing or inciting a female child under 16 to engage in sexual activity (offender 
aged 18 or over) - no penetration. 
21. Causing or inciting a male child under 16 to engage in sexual activity (offender 
aged 18 or over) - no penetration. 
 
70. Sexual activity etc. with a person with a mental disorder: 
1. 
Sexual activity with a male person with a mental disorder impeding choice – 
penetration. 

 
 
26
2. 
Sexual activity with a female person with a mental disorder impeding choice – 
penetration. 
3. 
Sexual activity with a male person with a mental disorder impeding choice - no 
penetration. 
4. 
Sexual activity with a female person with a mental disorder impeding choice - no 
penetration. 
5. 
Causing or inciting a male person with a mental disorder impeding choice to 
engage in sexual activity – penetration. 
6. 
Causing or inciting a female person with a mental disorder impeding choice to 
engage in sexual activity – penetration. 
7. 
Causing or inciting a male person with a mental disorder impeding choice to 
engage in sexual activity – penetration. 
8. 
Causing or inciting a female person with a mental disorder impeding choice to 
engage in sexual activity - no penetration. 
9. 
Engaging in sexual activity in the presence of a person with a mental disorder 
impeding choice. 
10. Causing a person with a mental disorder impeding choice to watch a sexual act. 
11. Inducement, threat or deception to procure sexual activity with a person with a 
mental disorder – penetration. 
12. Inducement, threat or deception to procure sexual activity with a person with a 
mental disorder - no penetration. 
13. Causing a person with a mental disorder to engage in sexual activity by 
inducement, threat or deception - penetration. 
14. Causing a person with a mental disorder to engage in sexual activity by 
inducement, threat or deception - no penetration. 
15. Engaging in sexual activity in the presence, procured by inducement, threat or 
deception, of a person with a mental disorder. 
16. Causing a person with a mental disorder to watch a sexual act by inducement, 
threat or deception. 
17. Care workers: Sexual activity with a male person with a mental disorder - 
penetration. 
18. Care workers: Sexual activity with a female person with a mental disorder - 
penetration. 
19. Care workers: Sexual activity with a male person with a mental disorder - no 
penetration. 
20. Care workers: Sexual activity with a female person with a mental disorder - no 
penetration. 
21. Care workers: Causing or inciting sexual activity (person with  a mental disorder) 
- penetration. 
22. Care workers: Causing or inciting sexual activity (person with a mental disorder) 
- no penetration. 
23. Care workers: Sexual activity in the presence of a person with a mental 
disorder. 
24. Care workers: Causing a person with a mental disorder impeding choice to 
watch a sexual act. 
 
71. Abuse of children through prostitution and pornography (previously child prostitution 
and pornography): 
1. 
Arranging or facilitating the commission of a child sex offence. 
2. 
Paying for sex with a female child under 13 - penetration  
3. 
Paying for sex with a male child under 13 - penetration  
4. 
Paying for sex with a female child under 16 - no penetration. 
5. 
Paying for sex with a male child under 16 - no penetration. 
6. 
Paying for sex with a female child aged 16 or 17. 
7. 
Paying for sex with a male child aged 16 or 17. 
8. 
Causing or inciting child prostitution or pornography - child aged 13-17. 
9. 
Controlling a child prostitute or a child involved in pornography - child aged 13-
17. 
10. Arranging or facilitating child prostitution or pornography - child aged 13-17. 
11. Causing or inciting child prostitution or pornography - child under 13. 
12. Controlling a child prostitute or child involved in pornography - child under 13. 
13. Arranging or facilitating child prostitution or pornography - child under 13. 

 
 
27
14. Paying for sex with a female child aged under 16 – penetration. 
15. Paying for sex with a male child aged under 16 – penetration. 
 
72. Trafficking for sexual exploitation: 
1. 
Arranging or facilitating arrival of a person into the UK for sexual exploitation 
(trafficking). 
2. 
Arranging or facilitating travel of a person within the UK for sexual exploitation 
(trafficking). 
3. 
Arranging or facilitating departure of a person from the UK for sexual 
exploitation (trafficking). 
 
Taking and driving away and related offences 
37. Aggravated vehicle taking: 
1. 
Where, owing to the driving of the vehicle, an accident occurs causing the death 
of any person. 
 
Other motoring offences 
4. 
Manslaughter, etc:  
4. 
Causing death by dangerous driving. 
8. 
(Offences) Causing death by careless or inconsiderate driving (Offences due to 
commence in Autumn 2007). 
 
Drink driving offences 
4. 
Manslaughter, etc.: 
6. 
Causing death by careless driving when under the influence of drink or drugs. 
 
Serious acquisitive offences 
 
Burglary 
1. Burglary in a dwelling with intent to commit or the commission of an offence 
triable only on indictment. 
2. Burglary in a dwelling with violence or the threat of violence. 
3. Other burglary in a dwelling. 
4. Aggravated burglary in a dwelling (including attempts). 
 
Robbery  
1. Robbery. 
2. Assault with intent to rob. 
 
Taking and driving away  
1. Aggravated taking where the vehicle was driven dangerously on a road or other 
public place. 
2. Aggravated taking where owing to the driving of the vehicle an accident occurred  
causing injury to any person or damage to any property other than the vehicle. 
 
Theft from or of vehicles  
1. Stealing from motor vehicles. 
2. Stealing from other vehicles. 
3. Theft of motor vehicle. 
4. Unauthorised taking of a motor vehicle. 

 
 
28
Appendix B: Glossary of terms 
Re-offending terms 
 
Cohort – this is the group of individuals whose re-offending is measured. 
 
Index offence – the index offence is the proven offence that leads to an 
offender being included in the cohort. 
 
Index disposal – the index disposal of the offender is the type of sentence 
the offender received for their index offence. 
 
Start point (index date) – this is the set point in time from when re-offences 
are measured. 
 
Follow-up period – this is the length of time proven re-offending is 
measured over. 
 
Waiting period – this is the additional time beyond the follow-up period to 
allow for offences committed towards the end of the follow-up period to be 
proved by a court conviction, caution, reprimand or final warning. 
 
Re-conviction – where an offender is convicted at court for an offence 
committed within a set follow-up period and convicted within either the 
follow-up period or waiting period. 
 
Proven re-offence – where an offender is convicted at court or receives 
some other form of criminal justice sanction for an offence committed within 
a set follow-up period and disposed of within either the follow-up period or 
waiting period. 
 
Cohort definition used in the Proven Re-offending Statistics Quarterly 
Bulletin – the proven re-offending cohort consists of all offenders 
discharged from custody, otherwise sanctioned at court, receiving a caution, 
reprimand or warning or tested positive for opiates or cocaine in each year. 
This cohort’s criminal history is collated and criminal behaviour is tracked 
over the following one year. Any offence committed in this one year period 
which is proven by a court conviction or out-of-court disposal (either in the 
one year period, or in a further six months waiting period) counts as a 
proven re-offence.  
Cohort definition used in the Local Adult Re-offending Quarterly 
Bulletin – the local adult re-offending measure takes a snapshot of all 
offenders, aged 18 or over, who are under probation supervision at the end 
of a quarter, and combines four such snapshots together. This cohort’s 
criminal history is collated and criminal behaviour is tracked over the 
following three months. Any offence committed in this three month period 
which is proven by a court conviction or out-of-court disposal (either in the 
three month period, or in a further three months waiting period) counts as a 
proven re-offence. The latest available publication is available at this link.   

 
 
29
 
Disposal (sentence type) 
 
Fine – a financial penalty imposed following conviction. 
 
Court orders – court orders include community sentences, community 
orders and suspended sentence orders supervised by the Probation 
Service. They do not include any pre or post release supervision. 
 
Criminal Justice Act 2003 (CJA03) – for offences committed on or after 4 
April 2005, the new community order replaced all existing community 
sentences for adults. The Act also introduced a new suspended sentence 
order for offences which pass the custody threshold. It also changed the 
release arrangements for prisoners. See Appendix A of Offender 
Management Caseload Statistics 2009 for more information. 
 
Community order – for offences committed on or after 4 April 2005, the 
new community order introduced under the CJA 2003 replaced all existing 
community sentences for those aged 18 years and over. This term refers to 
all court orders except suspended sentence orders and deferred sentences 
which may have a custodial component to the sentence. The court must add 
at least one, but could potentially add all 12 requirements depending on the 
offences and the offender. The requirements are: 
 
 unpaid work (formerly community service/community punishment) – a 
requirement to complete between 40 and 300 hours’ unpaid work; 
 
 activity – for example, to attend basic skills classes; 
 
 programme – there are several designed to reduce the prospects of 
re-offending; 
 
 prohibited activity – a requirement not do so something that is likely 
to lead to further offence or nuisance; 
 
 curfew – which is electronically monitored; 
 
 exclusion – this is not used frequently as there is no reliable 
electronic monitoring yet available; 
 
 residence – requirement to reside only where approved by probation 
officer; 
 
 mental health treatment (requires offender’s consent); 
 
 drug rehabilitation (requires offender’s consent); 
 
 alcohol treatment (requires offender’s consent); 
 
 supervision – meetings with probation officer to address 
needs/offending behaviour; and 

 
 
30
 
 attendance centre – between a minimum of 12 hours and a maximum 
of 36 in total which includes three hours of activity. 
 
Typically, the more serious the offence and the more extensive the 
offender’s needs, the more requirements there will be. Most orders will 
comprise of one or two requirements, but there are packages of several 
requirements available where required. The court tailors the order as 
appropriate and is guided by the Probation Service through a pre-sentence 
report. 
 
Suspended sentence order (SSO) – the CJA 2003 introduced a new 
suspended sentence order which is made up of the same requirements as a 
community order and, in the absence of breach is served wholly in the 
community supervised by the Probation Service. It consists of an 
‘operational period’ (the time for which the custodial sentence is suspended) 
and a ‘supervision period’ (the time during which any requirements take 
effect). Both may be between six months and two years and the ‘supervision 
period’ cannot be longer than the ‘operational period’, although it may be 
shorter. Failure to comply with the requirements of the order or commission 
of another offence will almost certainly result in a custodial sentence. 
 
Pre CJA03 Court Orders – Community sentences 
 
Community punishment order (CPO) – the offender is required to 
undertake unpaid community work. 
 
Community rehabilitation order (CRO) - a community sentence which 
may have additional requirements such as residence, probation centre 
attendance or treatment for drug, alcohol or mental health problems. 
 
Community punishment and rehabilitation order (CPRO) – a community 
sentence consisting of probation supervision alongside community 
punishment, with additional conditions like those of a community 
rehabilitation order. 
 
Custody – the offender is awarded a sentence to be served in prison or a 
Young Offenders Institute (YOI). If the offender is given a sentence of 12 
months or over, or is aged under 22 on release, the offender is supervised 
by the Probation Service on release. It is important to note that the sentence 
lengths and youth disposals awarded will be longer than the time served in 
custody. For more information please refer to Appendix A of Offender 
Management Caseload Statistics 2009. 
 
Short sentences (under 12 months) – those sentenced to under 12 
months (made under the Criminal Justice Act 1991) spend the first half of 
their sentence in prison and are then released and considered ‘at risk’ for 
the remaining period. This means they are under no positive obligations and 
do not report to the Probation Service, but if they commit a further 
imprisonable offence during the ‘at risk’ period, they can be made to serve 
the remainder of the sentence in addition to the punishment for the new 

 
 
31
offence. The exception to this is those aged 18 to 20 who have a minimum 
of three month’s supervision on release. 
 
Sentences of 12 months or over – the CJA03 created a distinction 
between standard determinate sentences and public protection sentences. 
Offenders sentenced to a standard determinate sentence serve the first half 
in prison and the second half in the community on licence. 
 
Youth disposal (sentence type) 
 
Reprimand or warning – a reprimand is a formal verbal warning given by a 
police officer to a juvenile offender who admits they are guilty for a minor 
first offence. A final warning is similar to a reprimand, but can be used for 
either the first or second offence, and includes an assessment of the 
juvenile to determine the causes of their offending behaviour and a 
programme of activities is designed to address them. Reprimands and 
warnings for youths were abolished under Legal Aid Sentencing and 
Punishment of Offenders Act 2012 with effect from 8 April 2013 and 
replaced with youth cautions. 
 
Youth cautions – are a formal out-of-court disposal that can be used as an 
alternative to prosecution for young offenders (aged 10 to 17) in certain 
circumstances. A Youth Caution may be given for any offence where the 
young offender admits an offence, there is sufficient evidence for a realistic 
prospect of conviction but it is not in the public interest to prosecute.  
 
First-tier penalties 
 
Discharge – a juvenile offender is given an absolute discharge when they 
admit guilt, or are found guilty, with no further action taken. An offender 
given a conditional discharge also receives no immediate punishment, but is 
given a set period during which, if they commit a further offence, they can 
be brought back to court and re-sentenced. 
 
 Fine – the size of the fine depends on the offence committed and the 
offender’s financial circumstances. In the case of juveniles under 16, 
the fine is the responsibility of the offender’s parent or carer. 
 Referral order – this is given to juveniles pleading guilty and for 
whom it is their first time at court (unless the offence is so serious it 
merits a custodial sentence or it is of a relatively minor nature). The 
offender is required to attend a Youth Offender Panel to agree a 
contract, aimed to repair the harm caused by the offence and 
address the causes of the offending behaviour. 
 Reparation order – the offender is required to repair the harm 
caused by their offence either directly to the victim or indirectly to the 
community. 
 
Youth Rehabilitation Order – a community sentence for juvenile offenders, 
which came into effect on 30 November 2009 as part of the Criminal Justice 

 
 
32
and Immigration Act 2008. It combines a number of sentences into one 
generic sentence and is the standard community sentence used for the 
majority of children and young people who offend. The following 
requirements can be attached to a Youth Rehabilitation Order (YRO): 
 
 activity requirement 
 
 curfew requirement 
 
 exclusion requirement 
 
 local authority residence requirement 
 
 education requirement 
 
 mental health treatment requirement 
 
 unpaid work requirement 
 
 drug testing requirement 
 
 intoxicating substance misuse requirement 
 
 supervision requirement 
 
 electronic monitoring requirement 
 
 prohibited activity requirement 
 
 drug treatment requirement 
 
 residence requirement 
 
 programme requirement 
 
 attendance centre requirement 
 
 intensive supervision and surveillance 
 
 intensive fostering 
 
The following community sentences are replaced by the YRO, but will 
continue to exist for those that committed an offence before 30 November 
2009. The YRO is only available for those that committed an offence on or 
after the 30 November 2009. 
 
 action plan order 
 
 curfew order 
 
 supervision order 

 
 
33
 
 supervision order and conditions 
 
 community punishment order 
 
 community punishment and rehabilitation order 
 
 attendance centre order 
 
 drug treatment and testing order 
 
 exclusion order 
 
 community rehabilitation order 
 
Prison categories 
 
Category B and category C prisons hold sentenced prisoners of their 
respective categories, including life sentenced prisoners. The regime 
focuses on programmes that address offending behaviour and provide 
education, vocational training and purposeful work for prisoners who will 
normally spend several years in one prison. 
 
High security prisons hold category A and B prisoners. Category A 
prisoners are managed by a process of dispersal, and these prisons also 
hold a proportion of category B prisoners for whom they provide a similar 
regime to a category B prison. The category B prisoners held in a High 
Security Prison are not necessarily any more dangerous or difficult to 
manage than those in category B prisons. 
 
Female prisons, as the name implies, hold female prisoners. Because of 
the smaller numbers, they are not divided into the same number of 
categories although there are variations in security levels. 
 
Local prisons serve the courts in the area. Historically their main function 
was to hold un-convicted and un-sentenced prisoners and, once a prisoner 
had been sentenced, to allocate them on to a category B, C or D prison as 
appropriate to serve their sentence. However, pressure on places means 
that many shorter term prisoners serve their entire sentence in a local 
prison, while longer term prisoners also complete some offending behaviour 
and training programmes there before moving on to lower security 
conditions. All local prisons operate to category B security standards. 
 
Open prisons have much lower levels of physical security and only hold 
category D prisoners. Many prisoners in open prisons will be allowed to go 
out of the prison on a daily basis to take part in voluntary or paid work in the 
community in preparation for their approaching release. 
 

 
 
34
 
Miscellaneous terms 
 
National Probation Service – the National Probation Service generally 
deals with those aged 18 years and over. (Those under 18 are mostly dealt 
with by Youth Offending Teams, answering to the Youth Justice Board.) 
They are responsible for supervising offenders who are given community 
sentences and suspended sentence orders by the courts, as well as 
offenders given custodial sentences, both pre and post their release. 
 
Police National Computer – the Police National Computer (PNC) is the 
police's administrative IT system used by all police forces in England and 
Wales and managed by the National Policing Improvement Agency. As with 
any large scale recording system the PNC is subject to possible errors with 
data entry and processing. The Ministry of Justice maintains a database 
based on weekly extracts of selected data from the PNC in order to compile 
statistics and conduct research on re-offending and criminal histories. The 
PNC largely covers recordable offences – these are all indictable and 
triable-either-way offences plus many of the more serious summary 
offences. All figures derived from the Ministry of Justice's PNC database, 
and in particular those for the most recent months, are likely to be revised 
as more information is recorded by the police. 
 
Recordable offences – recordable offences are those that the police are 
required to record on the PNC. They include all offences for which a 
custodial sentence can be given plus a range of other offences defined as 
recordable in legislation. They exclude a range of less serious summary 
offences, for example television licence evasion, driving without insurance, 
speeding and vehicle tax offences. 
 
Indictable and summary offences – summary offences are triable only by 
a magistrates’ court. This group includes motoring offences, common 
assault and criminal damage up to £5,000. More serious offences are 
classed either as triable-either-way (these can be tried either at the Crown 
Court or at a magistrates’ court and include criminal damage where the 
value is £5,000 or greater, theft and burglary) or indictable-only (the most 
serious offences that must be tried at the Crown Court; these ‘indictable-
only’ offences include murder, manslaughter, rape and robbery). The term 
indictable offences is used to refer to all triable-either-way and ‘indictable-
only’ offences. 
 
Offence group (based on new ONS crime classifications) – offences 
classified into 13 separate offence categories using the new Office for 
National Statistics (ONS) crime classifications.  

 
 
35
Appendix C: Comparison of the two measures of 
re-offending 
 
Figure A1 below compares how the three measures of re-offending (the 
headline proven re-offending measure and the early estimates of re-
offending) are constructed. It shows the period over which the re-offending 
cohort is formed, the time over which re-offending is measured, the 
additional time allowed for re-offending to be proven, and the time taken to 
collect and analyse the data, and then to publish. 
 
Figure A1: how the two re-offending measures are constructed 
 
 
 
Cohort formation 
Headline measure and early estimates: offenders enter the cohort when 
they receive a caution, a final warning or reprimand (juveniles), are given a 
non-custodial conviction or are released from custody in the cohort 
formation period shown. 
 
 
Re-offences 
Headline measure: A re-offence is counted if the offence occurs within the 
"Re-offences" period shown. This is within 12 months of entering the cohort. 
 
Early estimates: A re-offence is counted if the offence occurs within three 
months of entering the cohort for the early estimates measure and within 
three months following each of the four caseload snapshots for the local re-
offending measure. 
 
Re-offences proven 
Headline measure: For a re-offence to be counted it must also be proven 
within the "Re-offences proven" period shown. This is within six months of 
the re-offence. 
 
Early estimates and local adult re-offending: For a re-offence to be counted 
it must also be proven within the "Re-offences proven" period shown. This is 
within three months of the re-offence. 
 

 
 
36
Explanatory notes 
The United Kingdom Statistics Authority has designated these statistics as 
National Statistics, in accordance with the Statistics and Registration 
Service Act 2007 and signifying compliance with the Code of Practice for 
Official Statistics. 
Designation can be broadly interpreted to mean that the statistics: 
 meet identified user needs; 
 
 are well explained and readily accessible; 
 
 are produced according to sound methods; and 
 
 are managed impartially and objectively in the public interest. 
 
Once statistics have been designated as National Statistics it is a statutory 
requirement that the Code of Practice shall continue to be observed. 
 
Symbols used 
 
..  
Not available 
0 
Nil or less than half the final digit shown 
- 
Not applicable 
* 
One or both of the comparison figures are less than 30 
(p) 
Provisional data 
 

 
 
37
 
Contact details  
 
For queries, comments or further information, please contact: 
 
Nick Mavron 
Ministry of Justice 
Justice Statistics Analytical Services 
7th floor 
102 Petty France 
London 
SW1H 9AJ 
 
 
Email: xxx@xxx.xx 
 
Alternative formats are available on request from 
xxx@xxx.xx. 
 
 
 
 
 
 
 
 
 
 
© Crown copyright 2015 
 
This publication is licensed under the terms of the Open Government 
Licence v3.0 except where otherwise stated. To view this licence, visit 
nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to 
the Information Policy Team, The National Archives, Kew, London TW9 
4DU, or email: xxx@xxx.xx.