THE justice secretary, Jack Straw, was facing a scathing attack on Labour’s prison policy this weekend after it emerged that criminals on probation are charged with one in seven murders in Britain.

The Tories unearthed figures which show that in the past three years at least 300 criminals on parole have been charged with murder. A further 130 have faced trial for attempted murder or conspiracy.

Dominic Grieve, the shadow justice secretary, said the figures shattered Straw’s recent claim that the fiasco surrounding the brutal murder of two French students was a one-off case.

Gabriel Ferez and Laurent Bonomo, who were stabbed more than 200 times in a sadistic attack in London last June, were killed by Dano Sonnex and Nigel Farmer. Sonnex should have been in jail at the time in connection with an earlier crime he had committed while on probation.

“We are now learning the true scale of the systematic failings revealed in the tragic Sonnex case. Gordon Brown has released serious offenders early and relaxed the monitoring of those on probation,” Grieve said.

“Dangerous criminals under diluted probation supervision are now being charged with a shocking one in seven of all homicides in Britain. This amounts to a reckless dereliction of this government’s duty to protect the public.

“Only this week, the justice secretary claimed the Sonnex case was a one-off. This now looks complacent in the extreme, not least since the number of murders committed by those on probation is in fact rising,” he added.

The figures show that 129 criminals on parole were charged with murders in 2006-7. A further 107 faced murder charges in 2007-8, with an additional 64 charged in the six months to last September, the latest period for which figures are available.

Probation failures have proved a constant embarrassment to Labour ministers. They were highlighted by the killing of John Monckton, a City financier, at his home in Chelsea, London, in 2004.

He was killed by Damien Hanson and Elliot White, who were both supposed to be under the supervision of the probation service at the time.

After the Sonnex case, David Scott, the head of London probation, resigned. Straw insisted the failures which led to the murders could not be blamed on lack of resources.

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