DERBYSHIRE police have written off more than 12,000 crimes as not worth investigating – nearly 50% more than last year.

And figures revealed to the Evening Telegraph show this has been done despite the number of incidents reported to police in the county going down.

From November 2007 until October 2008, officers "screened out" 12,115 incidents – 3,750 more compared to the previous 12 months – as they felt there was a lack of evidence and little hope of identifying the offender.

According to a recent report it would have cost the force an extra £309,000 for officers to attend all the crimes that were screened out.

The extent of crime screening in Derbyshire was disclosed to the Evening Telegraph under the Freedom of Information Act.

Deputy Chief Constable Alan Goodwin said the force simply could not investigate every crime that was reported. He said: "As a force, we have to manage demand but also provide a level of reassurance to the public, which is of course a fine balancing act. We deal with around 80,000 crimes a year. Realistically, we cannot attend every one, nor is it necessarily a requirement to."

From November 1, 2007, until October 31, 2008, 12,115 incidents out of the 75,696 reported to the force were screened out. This included writing off 3,709 reports of damage or arson, 2,493 reports of thefts from cars and 925 burglaries.

During the same period from 2006 to 2007, Derbyshire police screened out 8,365 crimes when 81,694 were reported to the force.

Victims are informed when an investigation is closed and are also updated if new evidence comes to light resulting in the case being reopened.

Mr Goodwin said the force had to prioritise the crimes in order to respond to them quickly and that only minor crimes were abandoned, such as small thefts or low-level burglaries that no-one witnessed. Only one per cent of domestic burglaries were written off.

He said: "The level of response needed to each crime is assessed individually and in some circumstances, where it meets the set criteria and the complainant is satisfied, an officer will not attend.

"To be able to respond quickly and efficiently to crimes that require an officer to attend, we have to prioritise and as part of that process certain crimes are screened.

"It allows us to focus resources on crimes where there is a realistic chance of evidence being obtained and ultimately an arrest and charge.

"If further evidence or information comes to light then we are in a position to investigate further."

In November, Chief Constable Mick Creedon told the Evening Telegraph how the force needed an extra £4m, along with up to 300 extra officers, to be able to tackle growing problems such as terrorism and organised crime gangs.

He also said that because of the Government grant formula, Derbyshire police was under-funded by nearly £5m last year.

But despite being shortchanged by the Government and having to deal with growing pressures, a police spokeswoman said this was not the reason for screening out more crimes than last year.

She said: "There is no reason for the increase in crime screening in 2007-8 compared with 2006-7 because each crime is assessed individually before a decision is made as to whether it should be screened out."

A spokeswoman for Victim Support, a charity which helps people affected by crime, said the figures did not come as a surprise to the organisation.

She said: "The police have always had to make tough decisions on which crimes are worth spending time and money in trying to solve.

"Whether it is called screening out, rationing or making evidence-based judgments on the likelihood of catching someone, it amounts to the same thing.

"Overall it is why less than 5% of all crime ever ends in a conviction. However, if the police didn't do this, the alternative would be to investigate everything until a culprit was found.

"What is important is that the police make a considered judgement."

Patrick McLoughlin, MP for West Derbyshire, agreed that it was not possible for the force to investigate all incidents reported.

He said: "The force do need to be very open about what they are doing in terms of screening out crimes. No-one wants to see police time wasted on trying to investigate crimes that will not be solved.

"But I'm very reluctant to say that certain crimes should not be investigated, as incidents that may not seem important to a young person may be very distressing to an older person.

"We have to trust the judgement of the force."