Exploring the prison population over the long-term

Pressure in the prison population was building prior to the COVID-19 pandemic

The average daily prison population in 2023-24 was similar to that in 2009-10, with substantial changes beneath the headline figures over this time. Effects relating to the COVID-19 pandemic have contributed to the ongoing challenges, with the prison population growing over 2024 and exceeding 8,350 on several days in 2024 and early 2025. However, in addition to these more recent pressures which are not yet fully reflected in annual Accredited Official Statistics (as discussed in the Introduction), Figure 1 shows that the population was also increasing sharply in the years immediately preceding the pandemic. This suggests some of the challenges have longer-term drivers.

Figure 1: The prison population was growing in the years immediately before COVID-19, in addition to showing a more recent rise

Average daily prison population, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

The pre-pandemic rise affected both the sentenced and remand populations

Both the sentenced and remand populations increased prior to the COVID-19 pandemic. For example, as shown in Figure 2, in 2019-20 both were at the highest levels seen since 2011-12.

Figure 2: Both the sentenced and remand populations were growing before COVID-19
Average daily prison population, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

The sentenced population then fell during the pandemic, whilst the number on remand further increased. This inflated the proportion of prisoners accounted for by the remand population which ranged from 17 to 19% between 2009-10 and 2019-20 pandemic, to 23% by 2023-24, although this is down slightly from a peak of 25% in 2021-22.

Fewer individuals are now arriving at or experiencing prison each year than in 2009-10

Substantially fewer individuals are now arriving at or experiencing prison each year than in 2009-10. Despite this, with fewer people now also departing prison annually, the average daily population in 2023-24 was at a similar level as in 2009-10 and showed much more stability (in a relative sense) than the other measures over this period.

The proportion of people arriving to prison only once in the year has also increased from 73% in 2009-10 to 80% in 2023-24.

Figure 3: Substantially fewer individuals are now arriving at or experiencing prison each year

Prison population over time – number of unique individuals experiencing imprisonment, number of unique individuals arriving to prison, and average daily prison population each financial year, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

There are now fewer short-term and more long-term prisoners

Short-term prisoners now account for a much smaller proportion of the sentenced population. This proportion decreased steadily from 60% in 2009-10 to 53% in 2019-20. In 2020-21 the proportion fell sharply to 45% and has remained around this lower level since (e.g. 44% in 2023-24).

Conversely, those serving long-term sentences (4 or more years) or life and indeterminate sentences now account for a larger proportion.[1]

Figure 4: The proportion of the sentenced prison population accounted for by long-term prisoners has increased

Proportion of the average daily sentenced prison population, 2009-10 and 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

The average length of a custodial sentence given, excluding life and indeterminate sentences, increased by 31% between 2013-14 (295 days) and 2022-23 (386 days).[2] This trend is likely driven by complex and interacting factors. It is not certain that sentence length per se is increasing.

Sentence lengths “appear to” have increased

Sentence lengths appear to be increasing. The average sentence length has increased and there is a growing number and proportion of the prison population serving longer sentences.

Changes in the types of cases coming to court and the ways that cases are dealt with are factors that have contributed to an increase in the average sentence length:

• there are an increasing number of convictions in the courts for more serious offences like sexual crimes, which has led to an increase in the number of custodial sentences for such offences[3]
• there has been a decrease in the number of convictions in the court for less serious offences like crimes of dishonesty, which has led to a decrease in the number of custodial sentences for such offences[4]
• there has been a reduction in the number of short sentences handed down by the courts (e.g. through the Presumption Against Short Sentences)[5]

These factors also contribute to the increase in the long[6]er sentenced prison population:

• there are more people in prison with index offences of ‘Murder and culpable homicide’, and ‘Rape and attempted rape’ (as discussed later), both of which lead to life or long-term sentences

As well as this, there have been changes to the point at which long-term and short-term prisoners are released:

• the 2016 change to the release point for long-term prisoners has meant that long-term prisoners who are not recommended for release by the Parole Board have had to serve a greater proportion of their sentence in prison
• the 2025 change to the release point for short-term prisoners has meant that short-term prisoners have to serve a smaller proportion of their sentence in prison

To set this into context, Figure 5 shows trends in the prison population by index sentence plotted alongside key legislative changes. It shows for example a gradual rise in long-term prisoners (serving 4 < 10 years) following the Control of Release Act 2015. This act amended the automatic early release point for long-term prisoners. Prior to this act, most long-term prisoners were automatically released after serving two-thirds of their sentence. This change resulted in a change in the composition of the prison population which now comprises of more individuals on longer sentences and fewer on short sentences.

The period of the COVID-19 pandemic is also shown in Figure 5 (from March 2020 onwards). Public health measures to prevent the spread of COVID-19 had substantial impacts on the operation of the justice system and on the prison population.

Figure 5: The prison population has shown changes which have followed legislative changes and the COVID-19 pandemic

Average daily prison population, by index sentence, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

However, it is important to note that short sentences do still impact on the prison population

The overall volume of custodial sentences given decreased between 2013-14 and 2022-23. However, this coincided with a fall in all convictions over this time. As such, although there can be year to year fluctuation, the proportion of convictions resulting in a custodial sentence was the same in 2013-14 and 2022-23 (13%).[7]

The majority of custodial sentences given are still under a year, although this has fallen from 82% in 2013-14 to 73% in 2022-23. Recently published Scottish Government analysis found those given short sentences are a complex cohort and a significant number of people appear to be moving through the prison system with short sentences several times a year.[8]

The time people spend on remand has also increased

As well as the number of people on remand increasing, the time taken to depart from remand or transition into the sentenced population has increased. Much of the rise has occurred since the COVID-19 pandemic began and is related to the time-bar extension introduced during the pandemic. However, Figure 6 shows this is part of a longer-term trend which started in the years prior to the pandemic.

When we look at remand departures:

• 90% occurred within 98 days in 2019-20
• this rose to a peak of 90% occurring within 146 days in 2022-23
• this then fell to 109 days in 2023-24, but this position is still higher than the level seen pre-pandemic

For transitions from remand to the sentenced population:

• 90% occurred within 145 days in 2019-20
• this increased to 289 days in 2022-23
• this then fell to 278 days in 2023-24, but is still substantially higher than the position pre-pandemic

Time to departure for remand-only occupancy periods, and the time for those beginning an occupancy period on remand to transition to the sentenced population, 2009-10 to 2023-24

Source: Scottish Government – Scottish Prison Population Statistics 2023-24

Figure 7 shows more recent data outlining how long people who were on remand on 1 April 2025 had been there. It highlights that almost one third had been on remand for longer than 140 days.

Figure 7: A third of those on remand in April 2025 had been there for more than 140 days

The number of consecutive daily snapshots an individual on remand on the 1st April 2025 had held an overall remand legal status.

Source: Scottish Government – Safer Communities and Justice Statistics Report, April 2025

Although there are still a high volume of short stays on remand too

The number of short stays (less than 2 weeks) on remand before a departure has declined in the last 10 years. Nevertheless, the volume remains at a high level, as shown in Figure 8. For example, the number of ‘1 day or less’ stays increased to pre-pandemic levels in 2023-24.

Figure 8: The number of short stays on remand have fallen over the last decade

Time to departure for remand-only occupancy periods each year, 2013-14 to 2023-24

Source: Scottish Government – Scottish Prison Population Statistics 2023-24, Supplementary table O2

The composition of the prison population has changed markedly since 2009-10

In 2023-24, compared to 2009-10, there were:

• more prisoners with index offences relating to violent crime or sexual crime
• fewer prisoners with index offences relating to crimes of dishonesty or crimes against society

Prisoners with index offences in the Non-sexual crimes of violence (Group 1) or Sexual crimes (Group 2) categories accounted for two-thirds of the average daily population in 2023-24, up from half in 2009-10. These crimes typically attract longer sentences, with complex management challenges within the prison estate.

Figure 9: The number of people in prison for index offences relating to violent or sexual crime has increased since 2009-10
Average daily prison population for four largest index offence groups, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

An increase in prisoners with index offences of ‘Rape and attempted rape’ is largely responsible for the number of people in prison for Sexual crimes more than tripling since 2019-10

There were almost 900 more people in prison with an index offence of ‘Rape and attempted rape’ on an average day in 2023-24 compared to 2009-10.

‘Rape and attempted rape’ convictions attract long custodial sentences. The average sentence length given in 2022-23 was 2,533 days (just under 7 years).[9] This has been broadly stable since 2015-16. Therefore the growth in this cohort can be expected to have a cumulative and sustained impact on the size, composition and management of the prison population.

Figure 10: The number of people in prison with index offences of ‘Rape and attempted rape’ has risen markedly since 2009-10

Average daily prison population with index offences in Group 2 - Sexual crimes, 2009-10 to 2023-24

 

Source: Scottish Government - Scottish Prison Population Statistics

More people in prison for sexual crimes reflects higher volumes within the justice system

A larger prison population for sexual crimes reflects a larger number of such cases being handled by the justice system over the long term. For example:

• the volume of ‘Rape and attempted rape’ crimes being recorded and cleared up by the police has increased substantially since 2009-10[10]
• the number of people convicted for ‘Rape and attempted rape’ in 2022-23 reached a record high of 187 and was more than double the 2013-14 level (90), although the annual number fluctuates[11]     

The rise in the number of people in prison for index offences relating to violent crime also pre-dated the Pandemic

There were almost 300 more prisoners with index offences in the ‘Non-sexual crimes of violence’ category on an average day in 2023-24 compared to 2009-10. Both the sentenced and remand populations in prison for violent crime rose in the years before COVID-19 pandemic. However, the rise was less pronounced than that seen for ‘Sexual crime’, albeit from a much higher baseline position.

Figure 11: The number of people in prison for index offences relating to ‘Non-sexual crimes of violence’ has increased since 2009-10

Average daily prison population with index offences within Group 1 – Non-sexual crimes of violence (total, sentenced, remand), 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

The rise has not occurred equally across different offence categories so there have been notable changes to the composition of those in prison for index offences of violent crime

‘Common assault’ accounts for most violent crime recorded by the police[12], but relatively few convictions for this crime result in a prison sentence.[13] In contrast, around 50 to 60% of ‘Serious assault and attempted murder’ convictions led to custodial sentences each year in the decade between 2013-14 and 2022-23.[14] Therefore, less common types of violence exert a proportionately larger impact on the prison population and reviewing trends in sub-categories of violent crime can help us understand pressures.

Figure 12 shows that key developments since 2009-10 include:

• an increase in the number of prisoners with an index offence of ‘Murder and culpable homicide’
• the Domestic Abuse (Scotland) Act 2018 introducing a new (and growing) category of violent crime prisoners

Figure 12: Whilst there are more people in prison for index offences of ‘Murder and culpable homicide’, some other sub-categories of violence have shown more stability or decreased

Average daily prison population with selected index offences within Group 1 – Non-sexual crimes of violence, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

The number of prisoners with an index offence of ‘Murder and culpable homicide’ has grown considerably since 2009-10

There were almost 200 more people in prison with index offences of ‘Murder and culpable homicide’ on an average day in 2023-24 compared to 2009-10. This contrasts with a 30% fall in homicide victims over the same time.[15]

This cohort get the longest sentences so have a long-term impact on the estate – for example, murder attracts a life sentence. Therefore, the growth in such prisoners has contributed to the increase in the number and proportion of long-term prisoners. The average punishment length of life sentences given for murder in 2022-23 was 19.3 years. Since 2013-14 this average has generally been higher than the previous decade (e.g. 14.3 years in 2004-05, 16.7 years in 2008-09).[16]

Figure 13: The number of people in prison with index offences of ‘Murder and culpable homicide’ has increased by almost 200 since 2009-10

Average daily prison population with index offence of ‘Murder and culpable’ homicide (total, sentenced, remand), 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

Convictions under the Domestic the Abuse (Scotland) Act 2018 have also added to the prison population

Whilst accounting for a small proportion of prisoners with index offences of ‘Non-sexual crimes of violence’ overall (4%), the number in prison with index offences relating to the ‘Domestic Abuse (Scotland) Act’ has increased each year since legislation was introduced. It has grown from 25 on an average day in 2019-20 to 161 in 2023-24. This is a 534% increase. This reflects a rise in convictions under the Act, although most convictions do not result in a custodial sentence.[17]

The average sentence length for custodial sentences given for convictions under the Act has also increased from 363 days in 2019-20 to 611 in 2022-23.

It is important to note not all prisoners are necessarily ‘additional’ as a result of the Domestic Abuse (Scotland) Act. In its absence some might have been sentenced for pre-existing offences (like Common assault).

Those in prison for violent crime are now more likely to be older

The average population of people under 30 years old in prison with index offences for violent crime more than halved between 2009-10 and 2023-24 (from 1,992 to 894), whilst within this group the number of prisoners under 21 years old fell by 86% (from 603 to 84). Over the same period, the average population of prisoners with index offences of violent crime aged 30 and more than doubled (from 1,373 to 2,761). Taken together, this means the demographic composition of those in prison for violent crime has significantly changed. 

For example:

• the rise in prisoners with index offences of ‘Murder and culpable homicide’ has been driven by an increase in prisoners aged 30 and over. This chimes with wider statistics on people accused of homicide. Over the past 10 years, the median age of a person accused of homicide ranged between 29 and 35 years old. This is generally older than the preceding ten years, which ranged between 23 and 30 years old[18]
• Those in prison with index offences of ‘Serious assault and attempted murder’ are also now much more likely to be over 30. Again, this reflects evidence of an ageing cohort of offenders found in earlier Scottish Government research looking at how the nature of ‘Serious assault and attempted murder’ crimes recorded by the police changed between 2008-09 and 2017-18[19]

Table 1: People in prison for violent crime are now more likely to be older

Proportion of the average daily prison population aged 30 or over, by index offence, 2009-10 and 2023-24

Index offence	2009-10	2023-24
Group 1 - Non-sexual crimes of violence (all)	41%	76%
Murder and culpable homicide	49%	84%
Serious assault and attempted murder	36%	71%
Common assault	41%	75%

Source: Scottish Government - Scottish Prison Population Statistics

Looking wider than violent crime, the prison population as a whole has become much older since 2009-10

The average age of all in prison increased from 31.4 in 2009-10 to 37.8 in 2023-24. Almost half of prisoners in 2009-10 were under 30, compared to below a quarter in 2023-24.

Most people in prison with index offences of ‘Rape and attempted rape’ are also aged 30 or over (77% in 2023-24). So the rise in these prisoners (along with those imprisoned for ‘Murder and culpable homicide’) has contributed to the ageing of the overall population.

The older cohort may present challenges in terms of management within the estate and whether such prisoners require different responses to support progression and rehabilitation.

Figure 14: There are now many more prisoners aged 30 and over
Average daily prison population by age group, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

It is also important to consider other demographic characteristics of the prison population

Other characteristics which could impact on the management of the population and estate, progression, release and reintegration are also important to take account of. For example:

• Sex – the prison population is overwhelmingly comprised of males. Females have accounted for between 3% and 6% of the prison population since 2009-10
• Deprivation – almost half of prisoners still arrive from 20% most deprived areas, but this proportion has fallen (55% in 2009-10 to 49% in 2023-24)
• Disability – there has been little change in proportion of prisoners self-reporting as disabled (when missing data is excluded from earlier years). The number has increased from 2009-10 to 2023-24, but much of this may be accounted for by improved data. Nonetheless, an increasing number of people reporting as disabled could potentially introduce challenges across the prison estate. Recent research by the University of Glasgow also points to a high prevalence of historical significant head injuries amongst the male prison population[20]
• No fixed abode – the proportion of people arriving in prison with no fixed abode has increased from 2.6% in 2009-10 to 9.5% in 2023-24. This may present challenges for release and re-integration
• Adverse childhood experiences – the 2019 Scottish Prison Survey found a substantial proportion of prisoners reported adverse childhood experiences[21]

Relatedly, a Scottish Prison Service report in late 2024 noted that the prison population is becoming increasingly complex.[22] It highlighted that ‘[m]any individuals need to be accommodated separately for a variety of reasons i.e., due to people’s legal status, gender, offence type, protection status, and/or health care needs, as well as residents with individual management needs.’

There are now fewer people in prison for drug-related offences, but drugs still impact on prison population and estate

Since 2009-10 the average daily number of prisoners for an index offence of ‘Drugs – supply’ has more than halved.

Figure 15: Many fewer people in prison for index offences relating to drugs

Average daily prison population for index offences ‘Drugs - Supply’ and ‘Drugs – Possession’, 2009-10 to 2023-24

Source: Scottish Government - Scottish Prison Population Statistics

However, substance use is still a challenge for the prison population and estate. For example:

• in the 2024 Scottish Prison Survey, 49% of respondents said they used drugs in the community prior to coming into custody; 32% said they were under the influence of drugs at the time of the offence[23]
• 73% of tests at prisoner reception were positive for illegal drugs in Scottish Prison Service Drug Trend Testing in 2021/22; 29% at the point of liberation[24]
• the Scottish Government published research on ‘Understanding Substance Use and the Wider Support Needs of Scotland’s Prison Population’[25] in 2022 which noted that: “Research indicates that individuals in prisons are more likely to have a substance use problem than to not have one”  
• drug misuse deaths in prison custody have increased in the decade to 2022-23, mirroring general population trends[26]

The Scottish Prison Service recently published their ‘Alcohol and Drug Recovery Strategy 2024-2034’ which reiterated the challenges of drug and other substance misuse or addiction on the ‘safety and stability’ of the estate. It outlines a framework for improving outcomes for those living in prison through the prevention and reduction of alcohol and drug related harm. In addition to efforts within prison, efforts to tackle drug (and other substance) misuse in society as part of the wider public health agenda could have an impact on the prison population and, in turn, estate.

 

[1] The Scottish Prison Population Statistics count index sentences only. Overall sentence length trends are reported in the Scottish Government Justice Monthly Brief.