Prison population: position paper

Drivers of the prison population

The drivers of the prison population are multifaceted, as are the numerous societal and socioeconomic factors that drive criminal behaviour. Outcomes in individual cases depend on a range of factors and independent decision making is, rightly, at the heart of the Justice system and that makes it difficult to model and predict what the future prison population will be. 

We know some of the key longer term drivers that have contributed to the recent rise in the prison population, some of which are positive and show success within the justice and policing system, namely:

• an increase in average sentence lengths
• while there has been a longer term trend away from shorter sentences, these still make up a notable proportion of the sentences given
• the ending of automatic early release at the two thirds point for long term prisoners (sentences of 4 years or more) in 2016. Release now takes place six months before the end of the sentence for those not already granted parole
• previously under reported crime types such as domestic abuse and sexual offences have been reported and resulted in convictions and can attract lengthy custodial sentences
• the use of home detention curfew (HDC) decreased from a high point of around 420 in August 2010 to around 50 to 60 in late 2023. HDC allows certain risk assessed individuals to spend part of their sentence in the community, subject to licence conditions and curfew
• the post-pandemic court recovery programme has been resulting in an increased sentenced population, but is also helping to reduce the population of prisoners awaiting trial