It is a figure that is often quoted, and yet never fails to shock: of all the allegations of rape recorded by the police, only 6.5% result in a conviction on a charge of rape. Between 75% and 95% of rapes are not reported.
The low rate persists despite a string of initiatives, including new policy guidelines, specially trained police officers and prosecutors, and an increase in referral centres, where victims go for forensic examination and medical care.
Experts and campaigners say the problem stems from failures and prejudices at all stages of the system, from initial complaint to trial. It may start with police officers who are sceptical about the victim's story, perhaps because she has been drinking or was attacked by her partner, and either dismiss the complaint or make little effort to investigate. Prosecutors might be reluctant to take a case to court where they fear the victim lacks "credibility".
Juries, reflecting a belief among the public in a number of "rape myths", can be reluctant to convict. Research has found that a third of people in the UK believe a woman is partially or totally responsible for being raped if she has been flirtatious. Almost the same number think she should shoulder some blame if she was drunk. It is telling that while around 60% of cases that reach court lead to a conviction, most of these result from a guilty plea. Less than a quarter of all those charged with rape are convicted following a successful trial.
But the worst area for the attrition rate is during the police investigation, after the report of the crime but before any charge. Only a quarter of allegations end up in court. Home Office research found that the most common reasons charges were not brought were insufficient evidence - in 40% of cases - and the victim withdrawing her complaint, in 35% of cases.
The Without Consent report, published in 2007 by the independent inspectorates for the police and Crown Prosecution Service, was highly critical of the way police and prosecuting authorities deal with rape cases, finding that many officers had little specialist training and lacked awareness of the need to follow the relevant guidance.
Delays, "unpleasant environments", inappropriate behaviour by professionals, insensitive questioning and "judgmental or disbelieving attitudes" were all found to have been inflicted on victims.
• This article was amended on 19 August 2011. The original did not make clear that the reference to 6.5% was for reported rapes that resulted in a conviction on the charge of rape. This has been corrected. The figure of 6.5% was also wrongly compared with "34% of criminal cases generally". In fact the figure 34% was a misread reference in a press release by the solicitor general in 2008 that stated "34% of all [rape] cases prosecuted result in a conviction". The incorrect reference to "34% of criminal cases in general" has been deleted.
