## Introduction

The Ministry of Justice launched a consultation in November 2017 to seek users' views on formally establishing a definition for a "prolific" offender. Only one response to the consultation was received, which was supportive of the proposals to establish a definition for "prolific" offenders, and the age specific methodology identified. The definition of prolific offenders will follow the rules summarised below. 

Definition 
 
- 
they were aged 10-17 and had 4 or more 
previous convictions or cautions (20,690 offenders); 
Juvenile prolific: 
An offender is defined as a juvenile prolific if on their last appearance in the criminal justice system 
- 
they were aged 18-20, had a total of 8 or more previous convictions or cautions, and had less than 4 previous convictions or cautions when aged 18-20 (33,352 offenders); and 
- 
they were aged 21 or older, had less than 16 previous convictions or cautions, had less than 4 previous convictions or cautions when aged 18-20 and had 4 or more previous convictions or cautions when aged 10-17 (107,056) 
 
Young adult prolific: 
- 
they were aged 18-20, had a total of 8 or more previous convictions or cautions, and had at least 4 previous convictions or caution when aged 18-20 (8,109 offenders); and 
An offender is defined as a young adult prolific if on their last appearance in the criminal justice system 
- 
they were aged 21 or older, had a total of 16 or more previous convictions or cautions, had less than 8 previous convictions or cautions when aged 21 or older, and had 4 or more previous convictions or cautions when aged between 18 and 20 (110,373 offenders). 
 
- 
they were aged 21 or older, had a total of 16 or more previous convictions or cautions, and had 8 or more previous convictions or cautions when aged 21 or 
older (211,945 offenders). 
Adult prolific: 
An offender is defined as an adult prolific if on the last appearance in the criminal justice system 

 The full definition can be found at the link -offenders-2017.pdf This is the first in a series of analytical papers which will focus on understanding the nature of the prolific offender case mix, including establishing a profile of these offenders. A series of future analysis is planned which will allow us to delve deeper into this type of offender, with the potential to explore what is the effectiveness of different sentence types and the career paths of prolific offenders. 

## Key Findings

Based on the definition of a prolific offender presented in this paper, around 492,000 offenders meet the relevant criteria during the period 2000 to 2016. Of the cohort of prolific offenders 20,690 (4%) were juveniles (aged 10 - 17), 41,462 (8%) were young adults (aged 18-20) and 429,374 (87%) were adults (21 or older) at the time of their last appearance in the criminal justice system. 

 
 
Figure 1 shows the change in the offending population between prolific and non-prolific offenders in each year based on their last appearance in the criminal justice system. The proportion of prolific offenders remained fairly steady between 2000 and 2007 at around 3% to 5%, since then it has increased steadily and in 2016 accounted of 25% of all offenders. 

## Demographics

 
(1) 
Figures do not include offender where Gender is unknown 
(2) 
Police officer identified ethnic appearance 
 

## Age

Of all prolific offenders, 20,690 (4%) were aged 10 - 17, 41,462 (8%) were aged 18-20 and 429,374 (87%) were 21 or older at the time of their last appearance in criminal justice system. Understanding how an offender becomes "prolific" or when they are "prolific" is complex. For example, an adult having committed one offence as an adult and 17 as juvenile could not really be considered a prolific adult, but would certainly be a prolific juvenile. Based on that presumption around four fifths of seemingly prolific young adults, i.e. aged 18 to 20 and a quarter of adults, aged 21 or over, were actually only prolific as a juvenile. Similarly, a quarter of adults were actually prolific as young adults. The proportion of juvenile offenders in the prolific population almost halved between 2000 and 2016, falling from 42% to 24% over this period. In the non-prolific population the proportion of juveniles remained relative stable (at around 14% to 18%) between 2000 to 2008, after which it declined to 7% in 2016. 

## Gender

The majority (89%) of prolific offenders were male compared to 75% of non-prolific offenders. Only 11% of prolific offenders were female in contrast to 25% of non-prolific offenders. Female offenders are less likely to become a prolific, with 4% of female offenders going on be prolific compared to 11% of males. However, the proportion of females in the prolific population increased from 8% in 2000 to 10% in 2016, where as in the non-prolific population the proportion of females fell from 26% in 2000 to 19% in 2016. 

## Ethnic Appearance

88% of prolific offenders were identified to be of White ethnic appearance while 8% were identified to be of Black ethnic appearance. This distribution is similar with those found in the non-prolific group. In both the prolific and non-prolific cohorts a similar trend was seen. The proportion of offenders of White ethnic appearance in the prolific population fell from 91% in 2000 to 86% in 2016, compared to the non-prolific population which saw a fall from 81% in 2000 to 77% in 2016. The proportion of offenders of Black ethnic appearance doubled over the period, rising from 5% in 2000 to 10% in 2016 in the prolific population, and 4% in 2000 to 9% in 2016 in the non-prolific population. 

## Prolific Offending Behaviour Criminal Career History

 
(1) Excluding offenders aged under 9 at first offence (2) Excluding life imprisonment The youngest an offender started their criminal career was 9. This is because for the period covered by this analysis the age of criminal responsibility was 8 in Scotland, and any offending in Scotland is accounted for if the offender subsequently offends in England and Wales. It is also worth noting that for each age cohort, on average the age a prolific offender committed their first offence was as a teenager. Around 80% of prolific offenders received their first sanction under the age of 17 and all offenders had received at least one immediate custodial sentence during their criminal career. The sleeping time, i.e. between an offenders most recent conviction/caution and the last conviction/caution, ranged from one day to over 42 years, and was on average 3 years. As prolific offenders get older the length of time between offending seems to increase, with adult prolific offenders being reconvicted around every 2.2 years, compared to juvenile prolific offenders which was only 8 months. Periods of imprisonment will, in some cases, have contributed to long gaps between offences, however only 1 in 4 sentencing occasions results in a custodial sentence. On average, each prolific offender had 5 immediate custody sentences during their criminal career. 

## Offence And Disposal On The First And The Last Occasion

Prolific offenders were most likely to have started their criminal career with more minor offences such as theft (mainly shoplifting), summary offences or criminal damage and arson offences. Around 45% of prolific offenders committed a theft offence as their first offence while 21% of the non-prolific offenders started with the same offence type. At their last appearance in the Criminal Justice System prolific offenders were more likely to have committed a more serious offence such as violence or drug offences.  In contrast to the first offence the proportion of theft and criminal damage offences were reduced to 21% and 1% respectively.  The proportion of prolific offenders convicted or cautioned for violence against the person offences has increased to 45%, 63% for sexual offences and 45% for possession weapons offences on their last appearance in the criminal justice system compared to those convicted or cautioned for the same offences on the first appearance.  
Caution is the most common disposal given to first time offenders. However, prolific offenders, on conviction, are more likely to get a conditional discharge and community sentence for their first offence than non-prolific offenders.  For prolific offenders, community sentences and conditional discharges accounted for 38% of all disposals given for a first offence compared to just 18% for the non-prolific cohort. 

Prolific offenders are more likely to receive a more severe disposal on their last appearance in the criminal justice system; around 90% received a conviction compared to just 56% of non-prolific offenders.  A third of prolific offenders had received some sort of custodial sentence (i.e. immediate custody and suspended sentence) compared to a tenth given to non-prolific offenders. Caution is still the most common disposal given to the non-prolific offenders (45%) while only 11% were given to prolific offenders. 

## Offence And Disposal In The Whole Criminal History

 
1 This counts conviction and caution sentencing occasions including the index offence sentencing occasion Prolific offenders commit nearly 8 times as many offences as all other offenders. Prolific offenders have been sentenced, on average, to immediate custody 4.6 times, and despite being less than one tenth of the offending population they have been to prison more times than all other offenders combined. As an offender becomes prolific they are more likely to receive a custodial sentence, with 
25% receiving an immediate custodial sentence for their last offence, compared to 3% for their first offence. By comparison non-prolific offenders are more likely to receive a caution for their first (52%) and last offence (45%).