In some areas of country, for instance Nottinghamshire, up 30 per cent

Crime judged by the severity score is up almost 17 per cent since 2010-11

The hidden reality of rising violent and sexual crime was exposed yesterday by a new official method of ranking offences by their severity.

It reveals that while there has been a small increase in the volume of crime reported to the police, there has been a much bigger rise in the severity of offending.

Under the Crime Severity Score, unveiled by the Office for National Statistics, each type of offence has been given a rating according to its seriousness, using sentencing data, and the actual level of public harm it causes.

Crime as judged by the severity score is up by almost 17 per cent since 2010-11, according to the rankings

Crime as judged by the severity score is up by almost 17 per cent since 2010-11, according to the rankings. In some areas of the country, for instance Nottinghamshire, it is up 30 per cent.

By contrast, the number of crimes recorded by police per 1,000 people has risen much less sharply in England and Wales over the same period – from 75 to 79 per 1,000, a 4.6 per cent increase.

Under the new system, murder is given the top weighting – 7,979 points per offence – while cannabis possession has the lowest with three points.

Attempted murder is rated as the second most severe with 4,663, followed by aiding suicide and a number of rape offences.

Robbery is rated higher than child abduction, while immigration offences are given a slightly greater weighting than arson.

Part of the increase is believed to be the result of a surge in reported sex offences dating back decades in the wake of the Jimmy Savile scandal

As well as cannabis possession, other crimes with low weightings include soliciting for prostitution and criminal damage.

The ONS said the rise in severity was down to ‘large increases in violent and sexual offences’ reported to police alongside ‘a large decrease in theft offences’.

Part of the increase is believed to be the result of a surge in reported sex offences dating back decades in the wake of the Jimmy Savile scandal, but murders have also risen to a five-year high.

The rise is also due to police recording complaints more accurately after accusations of ‘fiddling’ figures to meet targets.

The ONS said: ‘Since recent recording improvements have focused particularly on violent crime and sexual offences (for which weights are typically higher), increases in crime recorded by the police are likely to be more pronounced in the Crime Severity Score than in standard crime counts.’

The number of crimes logged by police is still 20 per cent lower than in 2006-07 under the last Labour government.

But critics said budget reductions of 5 per cent imposed on spending at the Home Office and slashing the number of police officers by 17,000 since 2010 had exposed the crime surge.

Liberal Democrat leader Tim Farron said: ‘We are finally seeing the hidden crime wave affecting Britain. The Government need to stop slashing the budgets to the police and make sure we get bobbies back on the beat.

‘This Government has fallen asleep at the wheel and people are paying the price.’

The ‘weighting’ of each offence is based on the average number of days in jail that offenders serve – the tougher the sentence, the greater the score.

Liberal Democrat leader Tim Farron said: ‘We are finally seeing the hidden crime wave affecting Britain'

Once a weight has been calculated for each offence, it is multiplied by the number of incidents. That total is then divided by the population for the area in question to give the severity score.

The new ‘experimental’ crime harm index will be published alongside the traditional quarterly figures for the first time.

Overall, nearly 4.6million offences were reported to the police in the year to June, an annual rise of 7 per cent.

Policing minister Brandon Lewis said: ‘Police reform is working and crime has fallen by well over a quarter since 2010, according to the independent Crime Survey for England and Wales, while violence has reduced by 25 per cent.