Raksha, a 25-year-old sex worker in Mumbai, India. Vivek Prakash/Reuters Since her husband walked out on her a year ago, Sumana has commuted from a rented slum house in south-eastern Delhi to sit by a busy road in the city centre.

Dressed in a floral-print salwar kameez and with kohl around her eyes, she picks up two or three customers a day for sex.

Mostly they are car chauffeurs, who pay as little as 300 rupees ($4.80) a time. Some, she says, are generous or gentle, but there is also violence.

Sumana sticks to daylight hours. Her family thinks she has an office job, which is what she would prefer. But she has no education, and she will carry on until her teenage son finishes school. She knows soliciting is illegal — though the law is vague on prostitution itself. She understands the benefits of condoms, yet her customers rarely wear one.

Sumana has no pimp; nor was she trafficked. The same goes for Bina, a younger woman nearby who arranges to meet higher-paying men by phone: guards, drivers and cooks who pass around her number. She complains of long hours.

Officials say India has over 3 milllion sex workers. It is unclear how many, like Sumana and Bina, opt for the business because they need the money, and how many are forced by others. Bharati Dey, president of the All India Network of Sex Workers, argues that prostitution is a matter of choice, and that sex workers should have rights like anyone else.

An Indian sex worker watches a Hindu festival in Mumbai, India. Danish Siddiqui/Reuters The industry has grown as women, notably ill-educated rural migrants, enter India's labour market in larger numbers. Most find low-paid or casual work; for a minority, selling sex is a relatively well-paid option.

Ms Dey's and other groups want the sex trade brought out of the shadows. In April the UN's special rapporteur on violence against women said ending India's de facto criminalisation of sex workers would make them less vulnerable. Five years ago the Supreme Court said prostitution should be legalised.

So, now, does the National Commission for Women, a federal body, changing its previous stance. Its head, Lalitha Kumaramangalam, argues that a regulated industry could better stop forcible trafficking, including of children, improve hygiene among workers and clients and limit the spread of HIV and other diseases. On November 8th she will make the case before a special panel of the Supreme Court looking at amending the law.

Openness and regulation bring benefits. Mayank Austen Soofi, who has written in depth about the brothels of G.B. Road, a sprawling red-light district in Delhi dating back to the Mughal era, says that every sex worker he knows wants to be legal. Prostitutes today hesitate to approach doctors. They dread police harassment. And they fear their landlords will expel them.

Sex workers gather in a red light district in Mumbai. Punit Paranjpe/Reuters A priority should be ending forced prostitution, especially of children. Apne Aap, an anti-trafficking group, says brokers pay as little as 4,000 rupees to the families of village girls who are then raped by customers. Raids of brothels by NGOs and police to rescue victims often fail because families later return the children to the same brokers. In other cases girls and young women are tricked with promises of marriage. Apne Aap claims that over a third of all sex workers are under 18.

The organisation opposes legalisation, arguing that more demand for sex would lead to more trafficking. Instead, Apne Aap's campaign, "Cool Men Don't Buy Sex", is intended to reduce demand. If that looks unlikely to have much success, the prospects of legalisation appear slender, too. No politician is ready to champion the idea. The conservative Bharatiya Janata Party is unlikely to support it. Those selling sex will continue to live in the shadows.

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