The Director of Public Prosecution, Keir Starmer, is understandably keen to dispel the damaging myths and stereotypes which are associated with rape cases. “One such misplaced belief is that false allegations of rape and domestic violence are rife," he says.

It is probably true that the prevalence of such cases is often overestimated. Most credible research places false allegations at between about two and ten per cent of all complaints, the difference between a small minority and a tiny minority. However, the new review does not, and indeed cannot contribute any kind of estimate of the extent of false allegations, its methodology does not allow it.

The CPS research reviewed 132 suspected false rape allegations where the evidence of fabrication was strong enough to require a decision on pressing charges, either for perverting the course of justice or wasting police time. (There were also 27 cases relating to non-sexual domestic violence - for simplicity, I’m excluding them from this discussion). Only 35 suspected false rape allegations proceeded to court. The 132 cases represent less than one per cent of reported rapes.

Despite headline claims that false allegations are “few and far between,” these are only the cases where the evidence of falsification is strong. There were more than 16,000 reported rapes last year, of which 82 per cent did not go to trial. Proving a rape allegation to be false is no easier than proving one to be true, and for every case where there is enough evidence of fabrication to justify possible prosecution, there must be others where the allegation is false, but there is little or no evidence to prove that. How many such cases might there be? It is impossible to know for sure and this study makes no attempt to find out. Anyone who states confidently what the total number might be is speaking from faith, not evidence.

So the CPS review provides no clean, simple answers about the extent of false rape allegations. It is nonetheless valuable for the light it shines on the gruesome complexities. The case studies do not portray spiteful, malicious characters bent on blackmail or revenge, but a ragged bag of sorry stories. Around half are under 21, many have mental health issues or learning difficulties. False reports from over a third of the younger suspects were made by parents or partners, after a domestic lie spiralled out of control.

The cases echo a messy reality described in a recent paper in the British Journal of Criminology which observed that there is not even consensus on what is meant by a false allegation. Drawing upon interviews with police and prosecutors, Dr Candida Saunders distinguished between reports of rapes which had not occurred (false complaints) and reports of rape which contain falsehoods (false accounts).

False complaints, her interviewees suggested, are actually very rare, but reports which contain falsehoods are described as being common. A typical example might be a complainant who told police that she had only had one or two vodkas before tests revealed her to be eight times over the driving limit. Others lie as to the extent of their prior relationship with the alleged attacker, or the circumstances by which they came to be alone together. Such false accounts do not mean the complainant has not been raped, in most cases the assumption is that s/he has been, but they do damage the credibility of a witness and undermine prospects of successful prosecution. Saunders argues that many presumed false reports may actually be false accounts. If there is to be better understanding of the nature of false allegations among police, prosecutors and the public, this is the area where it should begin.

What do we know for sure about false allegations? Very little, beyond the fact that they do sometimes occur. In a judicial system that requires conviction beyond all reasonable doubt it is almost academic whether the proportion is one in a hundred or one in ten - each case must be judged on its merits. It is important to note that 84 per cent of the cases studied by CPS involved a specific, named individual as the alleged assailant. Each could be expected to suffer great distress as a result, and false allegations can and do destroy lives. The CPS is right, I believe, to ignore pleas from some feminist groups to end all prosecutions for false rape allegations which would leave victims of a serious crime without protection or justice. The CPS is also right to tend against prosecution in all but the most egregious cases, given the complexities and possibilities for miscarriage of justice involved.

There is another sense in which this debate is academic. Recent IPCC investigations into the Met’s Sapphire Unit revealed an appalling record of incompetence, inadequacy and occasional outright corruption in the investigation of rape complaints, and it would be dangerous to assume this is restricted to London. The significance of false allegations must be marginal when so many reports were barely investigated at all, where evidence wasn’t collected or was actively destroyed. Ensuring that our police forces are willing and able to investigate the cases before them with honesty, competence and commitment would be the best protection for victims of rape and of false allegations alike.