Sutton Guardian can exclusively reveal 539 rapes reported to police in just over 20 years remain unsolved.

Borough Commander Chief Superintendent David Snelling invited a reporter from this paper down to the police station, to explain why he believes the figures aren’t as alarming as they first appear when put into context.

The information shows every rape reported between 1992 and 2014 that remains unsolved, but does not provide further details about the nature of the attack or the investigation.

Chief Supt Snelling said: "Does 539 undetected offences mean there are 539 rapists walking around our borough? The answer is no.

"Rape covers a very broad series of offences. It may happen within a marriage, or we may have a stranger who has raped someone, like the recent case in Grove Park. 

"We have to look at individual cases.

"Sometimes when someone is arrested the Crown Prosecution Service says there is insufficient evidence to afford a realistic prospect of conviction, which doesn’t mean to say a rape didn’t happen."

He explained when a person reports a sexual attack and a suspect is subsequently detained, the case will be marked unsolved if the victim later decides not to pursue the case.  

This is the same for when police arrest someone but feel they have insufficient evidence to submit the case to the CPS.

The figures were released on Monday, February 2, after a freedom of information request was submitted in September last year.

Under the Freedom of Information Act the details should have been released within 20 working days. The figures were handed over more than four months later after repeated requests by the police for extra time.

The number of unsolved rapes reported annnually has gradually increased during a 22-year-period, with seven listed for 1992 compared to 29 last year.

The highest number was in 2011 when 50 cases were reported, all of which remain unsolved.

Chief Supt Snelling says the rise has come about because more victims are coming forward.

He said: "We welcome the increase in reporting because that shows greater confidence in us as a service.

"There is now a growing trend of victims of domestic abuse who are reporting an assault.

"When they go on to talk with police they will let us know about times they have been subjected to rape. 

"We are also seeing a growing trend of rapes being reported within abusive relationships.

"A lot of the victims have spoken out very positively about the support they have received from Sutton police. 

"It is very important for us to support the victims through a terrible set of circumstances that has befallen them."

A Sutton police spokesperson said many of the incidents could be ongoing investigations.