Rape victims who binge drink should be given extra legal protection, according to the West Midlands most senior prosecutor.

David Blundell said a drunken "yes" did not always mean "yes" in cases where excessive alcohol had been consumed. Alcohol was a frequent factor in adult rape and excessive consumption by victims had led to cases being abandoned.

He spoke out as new statistics, obtained by The Birmingham Post, revealed more than half of the rape cases referred to the Crown Prosecution Service in the region are dropped. In 2005/2006, a total of 258 cases was sent to the CPS by West Midlands Police. Of these, 150 were dropped at the pre-charge stage after specialist rape lawyers concluded there was an unrealistic prospect of a conviction at the crown court.

The CPS decided to prosecute 108 cases – a small proportion of the total rapes reported to police – leading to guilty verdicts against 54 rapists.

In the same period, 856 rapes, including attacks on teenagers and young children but excluding males, were recorded by West Midlands Police.

The national conviction rate for rape is only six per cent.

Under current interpretations of the law, drunken women are deemed to be capable of consenting to sex as long as they are conscious. But under proposals that may be announced in the Queen's Speech next month, juries will be asked to consider if a drunken rape victim is sober enough to give informed consent.

Mr Blundell, Chief Crown Prosecutor for the West Midlands, said the introduction of a new legal provision relating to drink would boost conviction rates for rape.

Backing calls to reform the issue of drunken consent, he said a woman might be so stupefied by alcohol that it was impossible for her to consent, regardless of what she might say or indicate.

"It is a question of protecting people. The extreme view is, 'It's their fault, they've got so drunk,' which is unsatisfactory in my view.

"Or, 'Well, they shouldn't have got so drunk but they do need protecting because they are very, very vulnerable when they are so drunk’. That's the balance."

However, he cautioned against pursuing rape prosecutions in alcohol-related cases if the evidence was insufficient.

Women Against Rape said the proposal would have a limited impact on improving conviction rates.

>> FOCUS: Richard McComb analyses the impact of alcohol in rape

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