Any young British woman considering a career in prostitution should give careful thought to location. The same applies, our prostitution law being the mess it is, to any pimp or trafficker aiming to maximise profits without fines, arrests and other loss-making interruptions.

In Leeds, for instance, the Holbeck area is now a pimp’s paradise, the police and council having decided not to apply the laws on soliciting and kerb crawling between the hours of 7pm and 7am. Councillor Mark Dobson has explained that, since prostitution will never stop being an “industry as old as time”, “it’s incumbent on us to make it as safe as possible”. In December, one of the women benefiting from this scheme, a 21-year-old Pole, Daria Pionko, was murdered, her body discovered on an industrial estate.

In Suffolk, however, police prefer to believe, like the Swedish government, that prostitution is not part of the natural order. After five young women were murdered by a regular sex buyer in 2006, Suffolk Constabulary’s then Det Supt Alan Caton responded with a Nordic-style plan. Although the legality of off-street prostitution ruled out a full “end demand” strategy, as pioneered in Sweden, Suffolk’s zero tolerance of kerb crawling, with multi-agency support for women, rather than criminalisation, virtually eliminated street prostitution.

Nottingham, too, differs from Leeds, with its own project to end street prostitution by targeting sex buyers and by helping, instead of persecuting, women who want to exit. Since 2004, almost 900 sex buyers have attended a deterrent one-day course, of whom only 27 are known to have reoffended. Sgt Neil Radford, of Nottinghamshire police, says the number of women in street prostitution has fallen over 10 years, from 300 to around 50. If Britain followed Sweden, Norway, Iceland, Northern Ireland, Canada – and potentially, France – in adopting a sex-buyer law, the trade could also be reduced off-street, where prostitution remains dangerous and exploitative or, as an all-party parliamentary group on prostitution put it in 2014, a “form of violence against women and girls”.

The group deplored a “near pandemic” of violence that goes unreported because women are criminalised. Under current law, women and girls who are already damaged by prostitution, whether by actual physical violence or psychological trauma, are further punished with fines for having put themselves in harm’s way. In 2013-14, there were more charges for loitering and soliciting than for the crimes of pimping, brothel keeping, kerb crawling and advertising prostitution combined. Buyers, as Sgt Radford has often observed, just walk away.

In its report, Shifting the Burden , the all-party group recommended the introduction, instead, of a sex-buyer offence, of following the Nordic model. It then asked End Demand , a campaign to end commercial sexual exploitation, to find out how this could be implemented. The resulting report, produced by a commission on the sex buyer law, is to be launched in parliament this week. This concludes – on the basis of evidence from Nottingham and Suffolk, as well as countries such as Sweden, which criminalise buyers – that a similar law is overdue here, to reduce both the human and economic cost of prostitution.

Having participated in that commission, along with, among others, Alan Caton and Diane Martin, a survivor of the sex trade who has helped others to exit, I find it harder than ever to understand how any politician, local or otherwise, would want to perpetuate, by legalising it, a trade so staggeringly unequal and so dependent on the trafficked and marginalised. In Germany, which did precisely that in 2002, the resulting brothels are warehouses of migrant women, pimped for bargain basement prices. Legalisation has failed, it turns out, both to inspire more gallantry in clients and to convince many German women that supplying oral and anal sex on demand could make a nice change from waitressing.

“I find it awful, this is not work, you don’t set out to be in prostitution”, says a Swedish psychologist Lisen Lindström, whom the commission met in Stockholm. She treats women in and exiting prostitution for the city’s social services. Post-traumatic stress is common. What of the women who protest they’re happy in prostitution? “So let them,” she says. “We don’t bother them. We let them be. The majority have had very bad experiences, so let the focus be on them.” And if it’s the career prostitutes’ right to work, unhindered by a sex buyer law? “What kind of union would fight for the right to be raped? If being a psychologist meant that I should be beaten up or raped sometimes, what would my union say about that?”

To legalise prostitution, as Sweden’s chancellor of justice, Anna Skarhed, also pointed out, is to normalise sexual discrimination and violence against women. The reaction to a young woman’s murder in England’s legalised “managed zone” in Leeds was certainly muted, for a country that gets exercised about domestic violence, forced marriages, child rape. Many women in prostitution were underage, visibly so, when they were first exploited. For them, the rules are different. One UK campaigner argued recently for the legalisation of co-working for women in prostitution, “as this is the main way in which they believe their safety will be enhanced”. That the inessential business of prostitution should be as synonymous with serious physical danger as it is with organised crime barely registers as anomalous. If there were consistency in health and safety alone, Leeds police would be insisting on hi-vis jackets and lanyards in their night-time “managed zone”.

The converse, says Skarhed, has been a steady normalising, in Sweden, of the principles underlying the sex buyer law. As enforcement, with exit services, has depleted the number of prostitutes in Sweden, so attitudes have shifted : 70% want to keep the law.

But as in Britain, a forceful lobby maintains that the sex buyer law represents a “whorephobic” attack on women’s self-determination, moreover one infinitely more threatening to their wellbeing, you gather, than the kindly traffickers – who make an annual £130m in the UK. On the contrary, says Patrik Cederlöf, Sweden’s national co-ordinator against prostitution and human trafficking; when they are not criminalised, women are more willing to report attacks. Incidentally, with decreased supply, prices for sex have risen: witness a neat ledger shown to the commission by a Swedish state prosecutor, Lars Ågren, documenting the massive profits enjoyed, prior to discovery, by a Polish outfit running 23 prostitutes. “They could charge double in Sweden than in Poland.” He adds: “The girls aren’t making money.”

It’s quite true, though, that sex buyer laws are lousy for pimps. That’s another reason why one should, I think, be introduced in Britain, in the way now backed by the all-party group and proposed to the new home affairs select committee prostitution inquiry. As with any big, ethically blighted industry, PRs for prostitution will respond with renewed attacks on its opponents, to add to despairing assurances, as in Leeds, of futility: the trade is “as old as time”. So, of course, was slavery.

Catherine Bennett