As the various initiatives to curb demand for commercial sex have forced attention on the purchaser, the pro-sex-work lobby has acquired a new hero. The 'disabled client' (note the gender neutral description) is used to garner support, sympathy and to promote a view of the sex buyer as a nice, deserving individual.

It is interesting to explore the type of disability these men are imagined to have by those whose sympathy is being sought. It is notable that the injured veteran and tragic young man figures keep recurring as examples—always heroic.

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To hear the way many apologists for the sex trade describe disabled sex buyers, one could easily get the impression that selling sex to disabled people is an altruistic service, akin to meals on wheels. But the focus on this largely mythical buyer obscures both the majority of 'undeserving' punters and the harms done to women.

In spring 2015, in a stiflingly hot TV studio in Manchester, England, I am sitting next to Laura Lee, who describes herself as a "part-time call girl" and "sex workers' rights activist". We are waiting to pre-record an episode of O'Brien, a national UK TV programme in which we will debate the topic "Should we decriminalise prostitution?"

As the warm-up act tries to put life into the studio audience, I look around to see who, aside from Lee and a sex trade survivor I had met previously, is fitted with a microphone. There are a couple of heavily made-up women carrying whips and wearing fetish gear, and, in the front row, a middle-aged woman sitting next to a young, severely disabled man in a wheelchair. I could have written the script for what happens next.

Lee, who is so hostile to the abolitionist law she is mounting a legal challenge against the Nordic model introduced by the Northern Irish government in 2015, speaks about how prostitution is a choice for most of the women involved. I speak of the failure of legalised and fully decriminalised regimes, and why I support the abolitionist law. And the survivor highlights the harms caused to the women who are bought and sold.

The cameras then switches around and focuses on the woman and the young man in the wheelchair. Her name is Veronica. She explains that John is her son, and that his back was broken in a car accident when he was five. As John approached puberty, Veronica began to worry about how he would meet his sexual needs.

"Should we have brothels on the high street?" asks host James O'Brien. "We should have brothels everywhere," replies Veronica, before describing how she had trawled the Internet looking for help with getting her son laid, speaking to "sex workers, escorts, prostitutes, anyone who knew about this". Eventually, having been told about the massive sex trade in Las Vegas, Veronica took the aptly named John to lose his virginity with several prostituted women.

"He had a lovely time," she says, with a cheeky twinkle in her eye. Laughter and clapping erupt from the audience. But there is more to come. "Didn't you buy him a brothel?" asks O'Brien. "So John, your mum bought you a brothel?"

"Yes," John gloats, "and I lived in the basement for three years. I learned about all the different aspects of prostitution, and the dodgy side and the seedy side of it. But every man has got a different fantasy."

"He wasn't allowed to partake with any of the girls in our brothel," interrupts Veronica, "because I didn't want a situation where we could incur exploitation. I didn't want him to be one of these guys—'Oh, I've got a brothel so I've got rights to these women'."

The peels of laughter coming from the audience—including from a clapping, animated Lee—mask the sounds of disgust and protest coming from the sex trade survivor.

This scene dramatised one of the most commonly used arguments against criminalising sex buyers. Pro-prostitution lobbyists claim that the Nordic model would, in effect, be criminalising 'disabled people'.

The argument holds that disabled people have a right to access to sex, with the implied premise that their disability somehow impairs their ability to form intimate relationships. This claim is one of the clearest examples of how the sex buyers' so-called 'human rights' have been placed above those of the prostituted woman.

The "sex workers' rights" lobby argues that when disabled sex buyers are denied recourse to prostitution, they are being denied their dignity, liberty and the right to know physical pleasure and true love. There is even a not-for-profit organisation called Touching Base in Australia, which exists to "foster connections between people with disabilities and sex workers, with a focus on access, discrimination, human rights, and legal issues, and the attitudinal barriers that these two marginalised communities face".

Underneath the liberal language, this is pandering presented as a social service. To make this argument more palatable, the "sex workers' rights" lobby claims that feminist abolitionists are denying the rights of sex workers to consent to prostitution and to practise their own agency.

The myth of the sympathetic disabled punter has even been accepted by Amnesty International (AI). In its 2014 draft policy document (leaked to me by an AI insider, and which I subsequently published in a national newspaper), AI also takes the line that disabled men have a right to access sex via prostitution: "For some—in particular persons with mobility or sensory disabilities or those with psycho-social disabilities that hamper social interactions—sex workers are persons with whom they feel safe enough to have a physical relationship or to express their sexuality. Some develop a stronger sense of self in their relationships with sex workers, improving their life enjoyment and dignity."

The suggestion that disabled people are considered so unattractive that they have to purchase sexual access to another human body is offensive enough in itself. Disability rights activists have long campaigned for better access to the venues where they might meet sexual partners, as well as a less prejudicial and conventional view of beauty.

With the sanitisation of the sex trade by the "sex workers' rights" lobby and their academic enablers, terms such as "agency" and "empowerment" are increasingly applied to those selling sex as well as purchasing, particularly if the buyer is associated with a marginalised community.

Critics of the abolitionist law have found the argument about disabled men being denied sexual pleasure very useful in their campaign. However, it is less helpful to disabled people.

Not only does it reinforce the problematic belief that anyone who does not fit the conventional standards of beauty and desirability is unable to access consensual sex and therefore needs to pay for it, it further suggests that disabled people's carers are responsible for ensuring their clients' sexual satisfaction.

This is already the case in Denmark, where prostitution was legalised in 1999, and there is now an expectation that carers working with physically disabled couples should facilitate sex between them if asked—for example, the carer may be expected to insert the penis of one into an orifice of the other.

This is an extract from Julie Bindel's new book The Pimping of Prostitution: Abolishing the Sex Work Myth, published by Palgrave Macmillan on 27 September 2017.

Julie Bindel is a renowned investigative journalist, and has written extensively on religious fundamentalism, violence against women, the international surrogacy trade, mail order brides, trafficking, and unsolved murders.