§ Simon Hughes
To ask the Secretary of State for the Home Department pursuant to his answer of 28 February 2003,Official Report, column 772W, on the Criminal Justice Bill, what research he used to reach his estimate of 1,000 additional prisoners. 
§ Hilary Benn
A model was developed by the Home Office Research Development and Statistics Directorate as part of the review of sentencing policy conducted by John Halliday (Making Punishments Work, published in July 2001). This model was then adapted for use in assessing the impact of the Criminal Justice Bill, focussing on those aspects of the reviews proposals that have been taken forward in the Bill, as well as additional proposals that have been developed following the publication of the review. The model considers the cost-benefits of the proposals, as well as the impacts on prison and probation workload. It uses published prison and probation statistics, and research evidence on the effectiveness of programmes in reducing re-offending. It is based on sentencing behaviour in 2000. The assumptions within the model were agreed with the relevant stakeholders such as the Prison Service, Probation Service and others. The projected net effect of implementation of the sentencing provisions in the Bill, of a small increase of about 1,000 in the prison population by 2009, was arrived at using the model. The impact is estimated to be about 500 once all the changes have been implemented and sufficient time has passed for their full effects to be seen.