The aim of this research was to collect evidence to outline the economic arguments for and against prison interventions and their alternatives, thereby answering the question:

Are prison sentences really a cost-beneficial way of reducing offending behaviour in those populations who are at risk of further offending?

The findings were as follows:

Drug Treatment Alternative to Prison Programme (DTAP) - divert non-violent drug-addicted offenders into community-based facilities. The residential programme includes intensive and individual group counselling using the dynamics of communal living to teach positive, personal and social values and behaviour. Vocational and educational programmes are integrated into the programme. Residents are supervised 24 hours a day and are subject to in-treatment monitoring.

Effectiveness at reducing re-offending, compared to prison
Offenders that receive residential drug treatment are 43 per cent less likely to re-offend after release than comparable offenders receiving prison sentences.

Cost: £5,299 per year
Savings to tax payer plus saving from fewer victim costs : £202,775

Intensive Supervision Programme - Surveillance-orientated diversion from prison

Effectiveness at reducing re-offending, compared to prison
Offenders that receive surveillance are 31 per cent less likely to re-offend after release than comparable offenders receiving prison sentences.

Cost: £5,947 per year
Savings to tax payer plus saving from fewer victim costs : £130,477

Surveillance with drug treatment - Intensive supervision programme with drug treatment, or house arrest with electronic monitoring and recommended treatment.

Effectiveness at reducing re-offending, compared to prison
Offenders that receive surveillance with drug treatment are 14 per cent less likely to re-offend after release than comparable offenders receiving prison sentences.

Cost: £8,604 per year
Savings to tax payer plus saving from fewer victim costs : £61,387