§ Lord Windleshamasked Her Majesty's Government:
Whether they will give the factual and statistical basis for the assumption in chapter 13.4 of the White Paper Protecting the Public: The Government's Strategy on Crime in England and Wales (Cm 3190) that the deterrent effect of the sentencing proposals on those who will become liable to mandatory penalties (i.e. offenders who have one qualifying conviction for serious violent or sex offences, or two qualifying convictions for trafficking in Class A drugs or domestic burglary) will reduce the requirement for prison places by 20 per cent.
§ Baroness BlatchThere is research evidence that both the certainty of imprisonment and the severity of the prison sentence have a deterrent effect on offending. Recent studies include Beyleveld (1980), Lewis (1986) and Burnett (1992). Exactly what the deterrent effect will be is a matter of judgement. But targeted measures of this sort have not been tried elsewhere and the Government believe that a strong deterrent effect of the order of 20 per cent. can be expected in relation to offenders who would on reoffending be liable to a mandatory penalty. No allowance has been made for the deterrent effect the proposals may have on other offenders (such as first time burglars).