When Richard Gere picked up Julia Roberts in his Lotus Esprit in Pretty Woman, it was the start of a great Hollywood romance. The classic prostitute with a heart of gold, she was transformed almost instantly into a glamous sex kitten, equally at home shopping on Rodeo Drive, decorating his arm at the opera in San Francisco or stamping the divots at a polo match. And, of course, there was a fairytale ending in which the corporate prince rescued the fair maiden as she promised to “rescue him right back”.

But if an English Gere — perhaps a hedge-fund manager trying to find Notting Hill in the dark — attempted a similar stunt in the brave new world of Jacqui Smith, the Home Secretary, he wouldn't be handing out strawberries in the hotel penthouse but having his mugshot taken at the nearest police station.

Yesterday Smith announced proposals to “name and shame” kerb-crawlers in a crackdown on prostitution. Paying for sex with a woman “controlled for another person's gain” could now result in a hefty fine and a criminal record. This would include any women who have pimps, as well as drug addicts “working” to pay off their dealers — in other words, most of Britain's 80,000 sex workers, according to government figures. Anyone who pays a prostitute knowing that she has been forcibly trafficked could also face rape charges.

Smith is a brave woman attempting to overturn, as she puts it, over 2,000 years of history. Herodotus talks about sacred prostitution in Babylon, where each woman had to have sex with a foreigner as a sign of maturity. In the book of Joshua, a prostitute in Jericho assisted Israelite spies in conquering Canaan. The Ancient Greeks encouraged prostitution as long as they paid taxes. In Britain in the Middle Ages, all forms of sexual activity outside marriage were seen as sinful by the Church but prostitution was tolerated because it was held to prevent the greater evils of rape, sodomy and masturbation.

Now, spurred on by the murders of prostitutes in Ipswich, the Government has decided to make prostitution a high-profile target.

Harriet Harman, the deputy leader of the Labour Party, who has spent years campaigning against payment for sex, says: “This is not a cottage industry any more. What we are talking about is serious organised crime. This is the only way to protect the vulnerable.”

Yesterday she was celebrating. “We will look back on the days when we allowed women's bodies to be bought as truly medieval,” she said. “In this day and age our aspirations should be so much higher than women for sale. You are protected from buying a faulty iron but you are allowed to buy sex — it's just wrong.”

The philosopher Baroness Warnock also welcomed the government plans. “Why does society tolerate prostitution? Why is the nastiness of buying sex so seldom noticed? Brothels are treated as a kind of joke,” she said.

There are already laws against trafficking and pimping, but the Government's proposals will put the blame on the buyers as well as those selling women for sex. The Poppy Project, which helps women who have been brought to Britain as “sex slaves”, has been pressing for action. Helen Atkins, the group's exiting prostitution development officer, says: “There is no point in just going for the pimps when there is a potentially limitless supply of traffickers and victims. We need to frighten off the clients. Prostitution has become part of a lads' night out — we need to scare the hell out of them.”

Julia (not her real name), whose daughter was “groomed” by a pimp from the age of 13, says that the new proposals would have helped her family if they had been in place ten years ago. One of her biggest frustrations as a mother was discovering how little power the police had to act against the pimps. Police, she says, were quick to arrest female prostitutes as “sitting ducks” but unwilling to devote resources to tackling the much more elusive pimps who were the root cause of prostitution. This, coupled with female sex workers' fear of giving evidence against the pimps, ensured that they considered themselves untouchable.

When Julia's daughter Gemma (not her real name) tried to get out of selling sex in massage parlours and hotels, she was beaten by her pimp and, on several occasions, raped. But like many girls who had been groomed from childhood, she saw the man as her “boyfriend” and, says her mother, was under his spell even though he was clearly involved with other women.

The new legislation expects men to question the backgrounds of the women they are paying for sex, and to realise that in doing so they may be exploiting vulnerable women.

So why has it taken so long to tackle the problem? Is it because Britain has a female Home Secretary for the first time, or because former home secretaries such as Michael Howard had always argued that such laws would be impossible to enforce?

Andy Hayman, former assistant commissioner of the Metropolitan Police, thinks that the new proposals are ludicrous. “The police have so many other priorities, such as knife crime,” he says. “They don't want to hound prostitutes who obviously need the money, or their clients, unless they are causing serious problems.

“What these women need is help. Many of them are drug addicts or behind with their rent; they already have criminal convictions so they can't find another job. They don't need to be forced farther underground. Most are already very co-operative, and they are great informers. Coppers will ignore this one.”

Another problem is that many prostitutes have argued vehemently against the measures that are supposed to be protecting them.

“This is an disaster for many working women,” says Virginia (not her real name), who works in a sex parlour in southeast England that is run by a middle-aged couple. “These measures will make our jobs far more dangerous. The couple I work for are not pimps, they check my clients and make sure I'm safe. The sex between my client and myself is a consensual act.”

Virginia, a teacher by training, became a prostitute six years ago when she was made redundant. “I had a large mortgage and I couldn't lose my home because I had two small daughters to care for,” she says. “I go to work and I perform a service. The pay is good and I can pick up my children from school - if I worked at Tesco I'd never see them. If I get a big gas bill I can do a few extra clients.”

She is angry at the idea of her clients being named and shamed. “Most of them are decent men, coming to me can save their marriage,” she says. “They can ask me to do things that they can't ask their wives. Their women may be too tired for sex or have other preoccupations. I can concentrate on them 100 per cent for an hour and boost their confidence. It is much better to pay for sex than to have a fling with your wife's friend.”

But isn't she an exception? “The majority of women in this business who I know are single mums trying to get some cash together,” she says. “We're not all drug addicts or slaves. Most of us are normal working women.”

Niki Adams, a spokeswoman for the English Collective of Prostitutes, is equally horrified by the proposals. “Prostitutes need to stick together in groups,” she says. “They benefit from having maids, who are usually older women who have been in the profession, looking after them, answering the phone, popping out to get them sandwiches and giving them advice. Most won't be able to find other jobs; they will be forced underground.”

She says that prostitutes are now terrified of ending up with the most unscrupulous pimps. “All this will do is hound the decent parlour owners. The Government is trying to take the moral high ground but it's a low blow for women who are struggling to make ends meet, whether they are from Croydon or Croatia.”

Virginia says: “This is the wrong time to bring in this legislation. Doesn't the Government know that we're going into a recession? For some women this is the only job left — no one else will buy their Christmas presents or pay for their parent's funeral or for their drugs.

“The bankers screw people for money and they get bailed out; we screw people for money and ministers throw up their hands in horror. Yet we're not doing any harm to anyone. I think the public have more sympathy for our plight than theirs.”

A survey by Ipsos MORI for the Government Equalities Office found that only 36 per cent of those questioned agreed that it should be illegal to pay for sex, while 47 per cent disagreed.

“Most women go into prostitution through debt, domestic violence and homelessness,” says Niki Adams. “We have one member whose husband beat her up and smashed up her house last Christmas. The only way she can support herself and her disabled daughter is through prostitution. The Government is telling her she is now a victim, but for the first time she is standing on her own two feet and feels safe. Ministers may try to tell her that what she does is as good as being raped, but she certainly knows the difference.”

Yet Jacqui Smith said yesterday that she was “proud to be helping the thousands of women coerced or trafficked into prostitution in our country”. And Harriet Harman has little sympathy for those who want to continue in the profession: “The majority of them are being exploited. The Government's job must be to protect the vulnerable.”

It is unlikely that the two women can stop the oldest profession in the world. But they will, at least, have made men think twice about their Pretty Woman fantasy.

Streets Ahead: what they do abroad

In 1999, when Sweden effectively made prostitution illegal by criminalising anyone who purchased sex, the rest of the world watched intently. One year later, the Netherlands went to the other extreme and legalised the industry. Both countries claim today that prostitution has decreased since its Nineties heyday.

In Sweden, the number of working prostitutes fell from an estimated 2,500 to 1,500 in the first five years of legislation. More than 500 clients, or “johns”, have been convicted and received fines of up to £5,600 or letters to their wives informing them that their husbands paid for sex. No one has yet been sent to jail.

In the Netherlands, supporters of legalisation claim that prostitutes, with their work permits, social security benefits and regulated brothels, are now much safer then if they had been driven underground by criminalisation. Not to mention, sexual transactions in Amsterdam alone draw in a taxable £66.5million a year to the local economy.

So which path is better? Certainly neither offers all the answers. A recent article in The Economist quoted an Amsterdam policeman as saying that more than 50 per cent of the women in the windows of the city's red light district were there under duress.

Criminal gangs from Eastern Europe and Russia have moved in to make the most of lax laws — laws that were intended to reduce trafficking, but instead appear to have encouraged it. And in Sweden, critics say that prostitution has been driven into the back rooms and on to the internet. “The Swedish sex-purchase law has increased violence against sex workers and makes it impossible for sex workers to work safely and securely,” reads the website for SANS, the Swedish sex workers and allies network in Sweden.

The network claims that since the 1999 legislation, violence against prostitutes has increased, as has the risk of contracting a sexually transmitted disease, because clients and prostitutes are afraid to seek treatment. Prostitutes' traditional support networks have broken down, leaving them on their own and open to exploitation.

The UK seems to be staking out the middle ground in this age-old policy dilemma. But it would be wise to take a hard look at Finland first. In June 2006 it became illegal for clients to purchase sex from a prostitute who was trafficked or being exploited.

There have been no official studies into the effectiveness of the new law but many of the country's experts do not support it. They point to the booming internet prostitution industry in Finland and the difficulties that the police face in proving that a client knew the prostitute was trafficked. Since the legislation came into effect, there has not been one single prosecution.

“No law will stop prostitution,” says Agneta Borg, a social worker in Stockholm who has been working with prostitutes for 40 years. “As long as there is a demand, there will be women selling themselves.”

Hannah Fletcher and Claudia Fromme

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