Joan Smith: A foul cocktail of rape, alcohol and cant

So it's back to the drawing-board, then, in the perennial search for the blameless rape victim. Since most of us are reluctant to stay indoors all the time, dressed in anti-rape suits that cover us from head to toe, there is always some purse-lipped moralist ready to declare that it's our own fault if we're forced to have sex against our will; hence the attractiveness in recent years of the notion that men are prowling bars, ready to spike our drinks with date-rape drugs such as Rohypnol, thus rendering us comatose and unable to fight them off.

I'm not saying it never happens, but I've always been suspicious of the motives behind all these lurid stories about women being drugged by charming strangers in pubs or at parties. (Remember their distant ancestor, the white slave trade?) Now my suspicions have been confirmed by a study carried out by the Association of Chief Police Officers (Acpo), which has found that many victims of sexual assault were drunk rather than drugged.

A study of 120 victims from November 2004 to October 2005 found no link to Rohypnol and evidence of another date-rape drug, GHB, in only two cases. All but one of the women said they had been drinking before they were assaulted, and almost half said they had taken a combination of recreational drugs and prescribed medication in addition to alcohol. "In most cases, the alleged victims had consumed alcohol voluntarily and, in some cases, to dangerous levels," said an Acpo spokesman.

Some people - I'm thinking again of my colleagues in the right-wing press - will doubtless respond to this research with a denunciation of the heavy-drinking culture of young British women. The sluts! How can they complain if they are unladylike enough to get legless, confusing all those poor men who quite naturally believe that any woman who is falling-down-drunk aspires to nothing more than to have sex with someone she's just met (or hasn't even met, in cases where a rapist follows a drunk woman from a bar).

You will not be surprised to learn that I don't subscribe to this view. On the contrary, it seems to me that while not many men are putting themselves to the trouble of acquiring prescription-only drugs, a sizeable number are prowling bars in search of women who have been drinking heavily and using alcohol to help them to become even more incapacitated. "The most common method of spiking drinks is alcohol," Det Ch Supt Dave Gee, a co-author of the Acpo report, confirmed yesterday.

In moral terms, this is just as bad as using drugs, but there is a world of difference in the way the two acts are regarded. In spite of the Home Office's correct insistence that rape is never the victim's fault, the tiny number of women who have been drugged attract sympathy in a way that drunk women don't; I've been shocked lately by the bile that's poured over women and girls who have been drinking, even if they're then subjected to the most horrific sexual assault, while a woman who's been slipped Rohypnol will be seen as entirely innocent.

What's going on here is an acknowledgement that rape is an awful crime, and that too many men - currently 19 out of 20 defendants who come before a court - are getting away with it. The problem is the victims, who simply don't conform to the standards of behaviour required of a woman if she is to have a hope in hell of seeing her attacker convicted. A woman who goes out drinking, who wears fashionable clothes, who dances with a man at a nightclub and then invites him into her apartment for coffee: this woman has broken every rule in Top Tips for Well-Behaved Rape Victims and she will be treated accordingly.

That's why the date-rape scenario, rare though it is, is so appealing to right-wing commentators, whose rigorous standards of judgement relax only when a victim is actually unconscious. The rest of the time, they are so busy wringing their hands over the appalling behaviour of modern women that they have barely a word to say about men, whose moral responsibility apparently does not extend to avoiding having sex with women who are too drunk to fight them off.

Disgust for women who drink alcohol has a long pedigree, traceable at least as far back as the second century AD, when the Roman poet Juvenal fulminated on the subject in his sixth satire. But we don't live in the Roman empire any more, and I don't see why it's so much worse for women to get drunk than it is for men. If a man goes to a few bars with his mates after work, gets separated from them and is mugged on the way home, we don't excuse the thieves who took his wallet; no defence barrister in his right mind is going to stand up in court and claim that his client truly believed that the victim wanted to be robbed.

Plenty of barristers, on the other hand, are prepared to say exactly that about a woman who blearily remembers a man having sex with her, even though she tried to protest. It's presented to juries as the thorniest of moral dilemmas, threatening to lead to grotesque miscarriages of justice, when the truth is that in most cases avoiding a rape charge couldn't be simpler. If you're in doubt about consent, don't have sex; what could be easier?

Only the most opportunistic man would go ahead in such circumstances, and to suggest otherwise is tantamount to arguing that the penalty for drinking too much is sexual assault. I guess there are people in the world who would go along with that, notably the Grand Mufti of Australia, who recently enlightened us with his view that unveiled women are the equivalent of "uncovered meat". Whether your average Daily Mail commentator would be happy to find him or herself sharing an opinion, as the saying goes, with an extreme Islamic cleric, is another matter.

What's important isn't the method predatory men use to make women vulnerable to sexual assault, but the fact that they are willing to employ substances to this end. It's easier than resorting to violence, and leaves less evidence, but there's no doubt in my mind that they should be convicted of rape. And the problem for everyone who believes it's a grey area is this: like most criminals, rapists are serial offenders. When they are let off because the victim was incapacitated, they become even more confident and move on to the next victim.

You may not like the fact that young women, or indeed women of any age, sometimes drink too much. I don't like the fact that when some of them become victims of sexual assault, people continually ask questions about alcohol, drugs, how they were dressed and so on. Stop moralising over the behaviour of victims, for god's sake, and start worrying about the number of men who are getting away with rape.