Are victims of crime getting a raw deal? Yes, according to Sir Paul Stephenson, the Metropolitan police commissioner. He is disturbed by the fact that overcrowding in prisons and bottlenecks in the courts mean too many thugs and burglars are getting away with what are in effect parking tickets.

“We’ve ended up cautioning far too many people,” he says in an interview with this newspaper, giving examples of cases in which even very violent offenders were let off with a caution. He is right to be concerned. People who are burgled or mugged do not expect to see the perpetrator let off scot-free with a smile on their face.

Official figures show that only 22% of first-time burglars are sent to prison. Only 20% of third-time burglary offenders get what is supposed to be the minimum sentence of three years. Public concern is genuine. Surveys show that fewer than two in five members of the public have confidence in the criminal justice system. A BBC Panorama programme tomorrow will report on widespread concerns about the system, from victims, lawyers and the police themselves.

Part of the problem is that the different authorities have different ways of administering non-custodial punishments. Some are straightforward police cautions. Others, such as conditional cautions, are issued by the Crown Prosecution Service. Keir Starmer, the director of public prosecutions, acknowledges that this breeds both confusion and dissatisfaction among victims. “I accept that what is needed is a coherent system across the board, with one overarching scheme,” he says.

What is to be done? There seems a simple solution. It is scandalous that victims are being denied justice because of a lack of capacity in our prisons and courts. The presumption should be that thugs and burglars will be locked up. We should build more prisons.

There is scope for some subtlety. We know that the one thing prisons are very good at is moulding lifetime criminals out of casual offenders. As schools of crime they do a better job than they do of rehabilitating.

This need not be the case. Today we report on an initiative by leading City figures led by Sir Ronald Cohen, a prominent Labour donor. It would entice investors into paying for the rehabilitation of offenders, with their return dependent on a reduction in re-offending rates. A pilot project is to be launched.

We cannot have criminals being seen to get away with minor punishments for serious crimes. Victims should not have to suffer a double trauma: first of the crime, then of the lack of punishment. When Britain’s most senior policeman says it is unacceptable, it is.