Data published by Police.uk has shown that an average of 70 per cent of alleged crimes reported across seven wards in Oxford between May 2018 and April this year were not prosecuted.

This could be for several reasons, such as a lack of evidence, no CCTV footage, forensics or witnesses.

In Oxford Central, Thames Valley Police recorded 4,787 crimes in the 12 months leading up to April, yet 3,363 of these – equivalent to 70.3 per cent - were not taken any further.

Out of the 3,363 closed cases, a total of 2,591 – (representing 54 per cent of overall crimes reported that year) were closed because no suspect was identified.

Police will close an investigation with no further action when: further investigation is deemed not to be in the public interest; the investigation is completed because no suspect was identified; or police are unable to prosecute the suspect.

The elected head of the force, Anthony Stansfeld, explained that whenever there is an opportunity to pursue a suspect and slash the statistics, police will do so.

However, each case has to be filed with the Crown Prosecution Service (CPS) to proceed and they ‘turn down more crimes than police would like’.

He said: “I am never satisfied with the numbers, I would like there to be better statistics across the Thames Valley.

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"But some of the crimes are non-existent, some we can’t get evidence of happening and some of them are reported more than once – they are very skewed statistics. The CPS turn down more crimes than we would like them to.”

The figures analysed show that the highest number of crimes reported across the city were violence and sexual offences, but Mr Stansfeld explained that a large number of violent crimes do not result in any injuries, which he considers a minor victory.

“But it is an alarming figure, because not everybody understands it," he added. "Any proper crime, I can assure you, gets investigated.

“We have to prioritise crime and we can’t prioritise everything. If a student loses a bike, we can’t launch a major investigation.”

Just under three per cent of crimes (139) in Oxford Central led to a suspected offender being sent to court.

Of those, 133 crimes led to a suspect being charged.

Elsewhere in the city, the majority of reports to police also resulted in ‘no further action’.

The city is divided up into seven main wards on police.uk. These are: Oxford Central, Barton and Risinghurst, Cowley, East Oxford (which covers Iffley Road), North Oxford (which covers Summertown, Cuttselowe and Wolvercote), North East Oxford (which covers Headington and Marston) and South East Oxford (which covers Blackbird Leys, Iffley and Littlemore).

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For the same year the figures for crimes filed under no further action were: Barton and Risinghurst 71 per cent, Cowley 68.9 per cent, East Oxford 73.4 per cent, North Oxford 71.9 per cent, North East Oxford 73.4 per cent and South East Oxford 68.8 per cent.

For each area, the majority of crimes reported to the police are violent or sexual offences, which includes common assaults, grievous bodily harm and sexual offences like rape.

This year in Oxford central there were 1,109 reports of this nature.

The high numbers are not exclusive to Thames Valley, but form part of a nationwide pattern.

A frequently asked question on Police.uk is: ‘Why does such a large proportion of crime result in no action being taken against the offenders?’

The answer given says a detailed assessment of the evidence often means that forces focus resources on offences which will lead to a prosecution.

The changing picture of how successfully police are catching criminals comes against a backdrop of rising crime stats in Oxford.

Mr Stansfeld said: “There are too many people in Oxford taking drugs. It is a really serious crime.

"We get people bringing drugs in from the West Midlands and London, and they wouldn’t if people didn’t take them - it has got to change.

"Thefts of cars has gone up, which can be put down to the manufacturers making them, but burglaries are at a low in Oxford at the moment. Last year they were up, but they’re going down.”

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He explained that more police funding from the government would be beneficial in slashing the double figures of unresolved crimes.

A spokesperson at Thames Valley Police said: “Thames Valley Police will always look to respond and carry out investigations whenever an offence is reported to us.

“There are a number of reasons why an offence can be filed as ‘no further action’ but it does not mean that no action has been taken or that a thorough investigation has not taken place.

“Further, if new evidence or information comes to light which enables us to progress the investigation, then we will do that.

“As a force, we have to prioritise certain crimes above others, based on threat, harm and risk to others.

“We are committed to carrying out investigations, and to bringing offenders to justice wherever possible."