Judges may be issued with new guidelines to ensure that they apply the law properly as to whether a drunken person alleging rape can be held to have consented.

Vera Baird, QC, the Solicitor-General, said it was “worrying” that some judges were dismissing rape allegations on the ground that an alleged victim had consented – even after a crucial Court of Appeal ruling in March.

Guidance to judges should make clear that sex is rape if the victim has lost his/her capacity to consent; and that this can be lost well before the victim is unconscious through drink. Equally, some people can consume substantial quantities of alcohol but not lose their capacity to choose whether to have sexual intercourse.

Announcing a package of reforms to boost the number of rape convictions, which “remains unacceptably low”, Ms Baird said that it was “very, very important that judges understand the law on capacity to consent”.

This had been clearly set out in the Court of Appeal case by Sir Igor Judge, Head of Criminal Justice. But it was not being “universally followed”. In his Court of Appeal ruling, Sir Igor said: “If, through drink, or for any other reason, the complainant has temporarily lost her capacity to choose whether to have intercourse on the relevant occasion, she is not consenting, and subject to questions about the defendant’s state of mind, if intercourse takes place, this would be rape.”

The court emphasised that, “as a matter of practical reality, capacity to consent may evaporate well before a complainant becomes unconscious”.

Ms Baird, a criminal barrister who has appeared in many rape trials, also announced that a panel of experts including judges and doctors was being set up to dispel the “myths” about rape victims. The group of academics, doctors and judges will meet for the first time next month to examine how to tackle jurors’ misconceptions.

“For example, juries sometimes find it difficult to understand why a rape has not been reported to police immediately when, in fact, it can take victims some time to decide to make a complaint,” she said. “Juries can think that she will be upset and very emotionally raw when she relives the episode for the court when, in fact, posttraumatic stress makes people seem unemotional and almost matter-of-fact. Someone who doesn’t know about this thinks that the person hasn’t been moved and that it was not the traumatic experience that it was.”

Her paper, published yesterday, is a response to government proposals for boosting rape convictions issued last year. At present 5.7 per cent of complaints to the police result in a conviction. Ms Baird pointed out that two years ago the figure was 5.2 per cent. It was “not much to swank about” but it showed perhaps that the measures in place were starting to have an impact.

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