Prison officials and penal reformers were taken by surprise by the timing of the initiative, which appears to have been rushed through to provide the Government with some much needed "positive news".
The measure, which was originally introduced by Michael Howard, the former Tory home secretary, will come into force in December. From that date an offender who carries out three domestic burglaries will automatically be sent to jail for three years, although in exceptional circumstances the courts can give longer or shorter prison terms.
The National Association of Probation Officers calculates that about 5,000 offenders areunder their supervision for three or more convictions for burglary. They estimate that about 8,000 people will have committed three house break-ins by 2004. The Home Office put the figure at 4,000 in the next 10 years - a figure widely ridiculed by penal groups.
The repeat burglars, who will serve 16 months of their three-year sentences, will fill the estimated 4,000 prison places freed by the extension of electronic tagging.
Jack Straw, the Home Secretary, made the announcement alongside details of a pounds 50m investment in burglary prevention schemes.
It emerged that the Prison Service knew about the decision only a few days ago. A series of emergency meetings was held at the Home Office on Monday.
Mr Straw denied he was returning to the Tory policy of "Prison Works", saying he had created a "sensible and balanced" programme combining prevention and punishment.
"This is the only effective way to reduce crime. Our approach to burglary makes it clear that we will both punish persistent burglars and act to prevent burglary in the first place," he said. Minimum jail terms would even out inconsistencies in sentencing across the country, he added.
The move immediately drew criticism from the opposition, with the Conservatives saying the Government was simply accepting Tory measures.
The Liberal Democrats warned that the fight against crime would be hampered by a drop in police numbers.
The three-year mandatory sentence was described as "a bombshell" by the Prison Reform Trust. Stephen Shaw, director, said mandatory penalties were "wrong in principle and likely to be disastrous in practice". He added: "The impact on the prison population is likely to be much greater than the 4,000."Reuse content