Justice sector agencies produce an annual forecast of the numbers of people held in prison for an eight year period. It projects the numbers of people expected to be held on remand awaiting trial or serving prison sentences. It draws on recent trends as well as the best available estimates of how those trends may change in future, on the basis of current legislation and policy. The annual prison population forecast is a key instrument for strategic planning within the Justice Sector. It is used to plan prison capacity needed for the future.
Justice sector agencies monitor trends in the prison population against the forecast, both for remand and sentenced prisoners. Changes in key variables that affect the forecast, such as the proportion of people convicted of criminal offences who are sentenced to prison, are monitored against their expected trends to identify how and why the prison population may diverge from the forecast in future.