IF Sir Paul Stephenson is feeling the strain towards the end of his first year as the country’s “top cop” — commissioner of the Metropolitan police — it doesn’t show. The 56-year-old Lancastrian exudes robust good health, which is amplified by his russet complexion. His colouring led a colleague when he arrived at the Met in 2005 as deputy commissioner to nickname him “Rusty”, and it has stuck.

Stephenson is anxious, however, to squash the persistent rumour that he is an aficionado of the tanning salon, when I raise it with him. “I have never been to a tanning salon in my life. I will turn colour if I walk past a lightbulb. If nothing else comes out of this interview, can we just put that [rumour] to bed?”

Any impatience on his part is understandable: there is a lot of substance he wants to get off his chest that goes to the heart of the debate on law and order — and is bound to play a big part in next year’s general election campaign.

Stephenson is deeply worried about the way efforts to unblock the courts and reduce prison overcrowding have led to the police being expected to act as a substitute justice system, handing out cautions and fixed penalties on an ever growing scale.

“The outcome of that has been an almost uncontrollable increase in cautions and the introduction of the fixed penalty ticket, which in the public’s mind equates to a parking ticket, which should not be [the case] with theft and thuggery.It’s put the police in the correctional business, instead of what we should be in, the law and order business, preventing and detecting crime. We’ve ended up cautioning far too many people. We’ve all come across examples — I’m personally aware of a recent case where a thug hit a smaller lad, from behind, without provocation, shifting his teeth. The shock felt by the victim and a number of people present was palpable. What was the outcome? [The assailant] received a police caution. I cannot imagine anyone would see this as justice.”

It’s cases such as this, says Stephenson, multiplied across the country, which result in the fact that “nationally the figures show that only 38% of citizens have confidence in the criminal justice system . . . If a huge thug comes and hits someone in the face for no reason and that person then gets off with a caution the following day because he’s expressed remorse when he’s sobered up, it’s fundamentally not right. It’s not right in the public’s mind. It’s not right in my mind . . . that someone [like that] is going to get away with what is basically a parking ticket.”

I point out that the public is also aware of how, even when persistent violent offenders are given custodial sentences, they are kept in jail for a much shorter period than the term stipulated by the courts, as prison governors attempt to ease the pressure on space in their cells.

“Prison governors have a difficult job, but I share the public disquiet that a victim thinks there is a certain sanction given, the court believes that the sanction is going to be carried out — and then it turns out to be something different. It’s hardly surprising that the victim becomes disappointed with the [justice] system.”

Earlier this year, the Ministry of Justice admitted that only 22% of those convicted of burglary for the first time received a prison term, or even a suspended custodial sentence. The government now claims to be adopting a tougher line with third-time offenders, but in practice only 20% are given even the so-called “minimum sentence” of three years.

In his gentle Lancastrian burr, Stephenson expresses his incredulity at such figures: “I happen to think that if you burgle a house there should be a clear expectation that you’re going to prison for doing it. Never mind third time; you should be there first time.”

So, after 12 years, has the Labour government failed to match up to its promise to be “tough on crime, tough on the causes of crime”? Stephenson’s face contorts into a slightly forced grin: “No comment.”

This was not an attempt at irony: the nation’s most senior policeman is determined, if nothing else, to avoid the pratfalls of his predecessor, Sir Ian Blair, an Oxford-educated would-be thespian who seemed to relish plunging into the political debates over such issues as compulsory identity cards and extending detention without charge to 90 days — on both of which he explicitly sided with the government, to the fury of the Tories.

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