Efforts by politicians of both main political parties to persuade the public that crime is falling have been bedevilled by the lack of confidence in police and Home Office statistics.

As Louise Casey said in her report on how to get the public engaged in fighting crime, which was published earlier this year: "The majority do not feel that crime has fallen”.

Today’s admission by the Home Office that police have for years been failing to properly record serious violent crime is a further blow to those efforts.

It gives ammunition to those who argue that the crime figures — both police recorded crime and the British Crime Survey — are manipulated.

However, the statistical controversy disclosed by an embarrassed Home Office today does not show that overall violent crime is rising.

The crimes recorded by police under "other violence against the person" should have been put in the category of "most serious violence against the person". As a result the rise in most serious violence is from 4,500 offences to 5,500 crimes.

Instead of putting grievous bodily harm with intent where there was no injury in the more serious violent category, police forces in England and Wales have put it in the less violent category alongside assault occasioning actual bodily harm.

As a result the proportion of serious violent crimes has been underestimated in official recorded crime figures by up to one fifth for years. This is deeply embarrassing for the Government which has always insisted that serious violent crime is the issue of most concern to the public.

It could be argued that police are simply being sensible. If a grievous bodily harm with intent attack results in no injury, it may seem appropriate to categorise it as a less serious violent crime.

But that is not what the Home Office guidance on police recording says.

The damage to public confidence of today’s disclosure goes much deeper than the simple admission that police forces have not been recording crimes in the right category.

The Home Office was unable to say how long this had been going on but it looks as if the misrecording could have been taking place for a decade.

Officials said that crime recording by police was assessed by the Audit Commission and Her Majesty’s Inspectorate of Constabulary to ensure that they were abiding by national standards. Just how both those organisations missed the misrecording of grievous bodily harm with intent offences was left unexplained.

But it hardly provides assurance that there is not other misrecording taking place.

Neither is the Government’s attempt to explain the problem helped by their suggestion that the mistake involved 17 forces, which they refused to name. That was contradicted by the police who said that it affects all 43 forces “to a lesser or greater extent”.

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