Drunks who force themselves on wives or girlfriends should face 'sex breathalyser' and rape charge, says government adviser Last updated at 9:51 PM on 14th December 2009 Drunk men who force their wives or girlfriends to have sex should be prosecuted for rape, the head of a Government inquiry into sex crime said yesterday. Drinking by the man should be considered an 'aggravating factor' when any woman makes a complaint of rape, said Baroness Stern. She added: 'Being drunk is voluntary and people who become drunk are responsible for their actions. Colleagues kiss under the mistletoe at the Christmas party (picture posed by models). Baroness Stern has warned that alcohol cannot be used as an excuse for rape 'It is not the alcohol that commits the rape. It is not an excuse. It used to be regarded as such, but it is not.' Her call for police, prosecutors and the courts to consider how much alcohol a man has consumed raised the prospect of a 'sex breathalyser' that would help decide when sex has become a crime. A similar idea has already been put forward by ministers, who said it should be a crime for a man to have sex with a woman who was very drunk. Judges quashed the plan. Baroness Stern, who is heading a review into how rape cases are handled by police and prosecutors But Lady Stern also told the London Evening Standard a drunken woman was not 'fair game' for men. The former prison reform campaigner is running an inquiry for Women and Equality Minister Harriet Harman into the way rape complaints are handled by police, the Crown Prosecution Service and other public authorities. Ministers are concerned at the low conviction rate for rapes. They hope to encourage more women to make complaints and 'fairly' increase convictions. Alcohol is thought to be involved in two out of three alleged rapes. Most also involve a man and a woman who know each other rather than an attack by a stranger. In 2003 Ministers changed the definition of rape so a man had to show he had reasonable grounds to believe he had been given consent. They argued that a woman who was very drunk was not capable of giving consent. But a series of cases showed that juries were reluctant to convict a man on the word of an alleged victim who was drunk and Appeal Court judges ruled that even a drunken woman could still consent to sex. Lady Stern's suggestion echoes comments by Victims' Champion Sara Payne earlier this month. Mrs Payne said some people felt women were too often warned about the risk of rape if they drink too much. In a report for the Home Office she said: 'The advertising we have had puts all the onus on the victim - it's "don't go out and get drunk, you might get raped". The onus needs to be on the man.' But criminologist David Green, of the Civitas think-tank, warned that the law should not treat men and women differently. 'If a man is responsible for his conduct when drunk, so is a woman,' Dr Green said. 'The law must be applied equally. It is a choice to get drunk, but it follows that the consequence of that choice applies to both sides.'