In the past two decades, the number of (overwhelmingly female) sex workers has more than doubled to 400,000, according to some estimates. And you don't have to go to Hamburg's notorious Reeperbahn street to find them. Berlin alone has some 500 brothels; Osnabruck, a small university city, has 70; and another 3000 or so exist across the rest of the country. Their neon-red lights and windowless facades dot even picturesque little towns known primarily for their cuckoo clocks and gingerbread.

The Pascha brothel in Cologne, for example, services an estimated 800 men every day. The 12-storey building, open 24 hours a day, is the biggest whorehouse in Germany, with 126 rooms as well as a restaurant, beauty salon, boutique, launderette, tanning studio and several bistros. About 150 women work there, supported by 90 other staff. An entire floor is dedicated to transsexual services.

Every day, more than a million men in Germany visit sex workers - most of whom hail from poorer neighbouring countries such as Romania and Ukraine. The country has become a prime destination for male sex tourists looking for cheap, legal and relatively hygienic pleasures of the flesh. Busloads of pleasure seekers from nearby countries - even, now, from the Netherlands, a country once known for its lax attitude towards prostitution - simply cross the border into Germany instead of travelling to faraway sex-tourism destinations such as Thailand. All told, the German sex industry rakes in some $US17.7 billion ($19.5 billion) a year.

The battle lines on commercial sex services confound the usual political fronts, pitting feminist against feminist, and putting human rights activists and church officials on one side of the barricades and social workers on the other. The incoming German government - a centrist coalition led by Angela Merkel's Christian Democrats - dared to broach the subject during coalition negotiations, only to drop it again pretty quickly in light of the ensuing brouhaha: There simply isn't a consensus within either party about what to do about it. Prostitution, it turns out, is a tricky problem to get right, and a decade after instituting one of Europe's most liberal laws governing the industry, Germany is no closer to being there.

At the centre of the storm are the "progressive" prostitution laws that Germany's Social Democrat-Green administration passed in 2002. The idea was to bring sex workers in from the murky underworld of red light milieus and give them rights and social benefits that would improve their working conditions. In theory, this should have prised them loose from pimps and mafia structures, even if it legalised the "promotional" activities of middlemen in the process.

Under current law, sex workers can sue for wages, pay into social security and demand that employers help pay for health insurance. The sex industry, never strictly illegal, had long paid taxes, but prostitution was not considered legitimate work. The goal was to make prostitution a job like any other. This way, the liberal politicos thought, women could be rescued from evils such as human trafficking. The legislation was meant to set in motion full-scale legalisation and aboveboard regulation of the industry, making sex workers as legit as bakers or physical therapists. But conservative opposition stalled the process, stranding it in the grey zone where it has remained since.

A decade down the road, almost nobody is happy with the result. Although the numbers are all estimates - reflecting a very un-Germanic shortage of research - there is little evidence that the plight of sex workers has improved, though it's clear that the sex industry itself is flourishing.

Prostitutes do have more rights, but they rarely avail themselves of them. Most sex workers still don't register as such, and few speak out against their handlers. Only very rarely, say police officials, do sex workers file criminal complaints against pimps. German statistics for human trafficking are also woefully incomplete: The German Federal Office of Criminal Investigation logged 987 victims in 2001 and 482 in 2011. How many of them had backgrounds in red light milieus is anyone's guess, and the figures are surely just the tip of the iceberg in terms of trafficking, especially via eastern Europe.

With evidence piling up that the decade-old prostitution law has failed - or at best, been a wash - a growing chorus of Germans is trying to ban the practice outright. Alice Schwarzer, a best-selling author and Germany's feminist-in-chief, has been at the forefront of this movement. In her view, prostitution is a straightforward human rights violation and should be outlawed as it has been in Sweden and, more recently, in France.

The 2002 laws protect pimps, Ms Schwarzer says, not prostitutes, whose plight has only got worse - a point echoed by many law enforcement officials. According to Ms Schwarzer, sex work is on a par with slavery, and its clientele and handlers should be treated like the criminals that they are. "Ninety per cent of prostitutes are forced into the sex industry through poverty and trafficking," she argues in her new book, Prostitution: ein deutscher Skandal, the publication of which kicked off a nationwide campaign against prostitution this year. At her urging, more than 100 big-name actors, artists, politicians and church figures signed a petition calling for a ban on prostitution. The Brussels-based European Women's Lobby is also on board, as is the women's liberationists' onetime nemesis, the Catholic Church.

Abolitionists have relied heavily on the firsthand testimonials of former prostitutes. Their graphic stories of abuse, exploitation and shattered lives are gut-wrenching. Some women tell of regularly being forced to have sex with as many as 60 men a day at the Pussy Club near Stuttgart. Others tell of group sex situations in which several men would have anal, oral and vaginal sex with them at the same time.

These women's passports are confiscated, their movements controlled, and their living conditions squalid. The lion's share of their earnings, meanwhile, is pocketed by the middlemen.

There's no doubt that these stories are true. The question is whether they are representative of the average sex worker. Ms Schwarzer says they are; her critics say they aren't.

There is a formidable array of well-informed German and international observers who think that Ms Schwarzer is well off the mark. They may not share her media canny, but when the two camps do battle on talk shows, the sparks often fly. One particularly raucous public discussion in November in Berlin degenerated into tumult. Pro-prostitution groups such as Sexworker, Hydra and Dona Carmen, which include many sex workers and former professionals, had members scattered through the audience who booed and jeered Ms Schwarzer, hoisting symbolic red umbrellas and banners reading: "Our Profession Belongs to Us!"

As is often the case, Ms Schwarzer was flanked on stage by a big-city police chief and former sex workers. When the latter spoke, the activists in the crowd shook signs reading: "You Don't Speak for Us!" At the end of it all, one activist, naked from the waist down, stormed on stage.

The sex worker groups are a welcome addition to a debate that until now has largely been conducted over the heads of those involved. These groups, together with other defenders of the 2002 changes, argue that Ms Schwarzer's numbers are bogus, that most sex workers in Germany choose their profession voluntarily, and that what is needed is more openness, not less. Unsurprisingly, many sex workers object to the notion that they are helpless victims: "We don't need to be saved" is one of their slogans.

The contention that most sex workers are trafficked and then held against their will is a red herring, argues Juanita Rosina Henning of Dona Carmen, a group that provides sex workers with rights-based counsel. "I've conducted studies myself in which I've gone into brothels and interviewed the women," she told left-wing daily Die Tageszeitung. "Over 90 per cent told me they knew they were coming to Germany to work as prostitutes."

"It's telling that these groups accuse the likes of Alice Schwarzer of denying them the ability to exercise their own free will," says Mariam Lau, a columnist for the weekly Die Zeit, who advocates reform of the present law. "It's like the way the left used to talk about the working class - that it has to speak for them because they hadn't developed the right consciousness yet. These women have their own minds and volition."

The sex worker groups, among many others, argue that outlawing prostitution has never worked and that doing so will only turn sex workers into criminals and force the industry back underground. The vast majority of male clients, they claim, are composed of decent-enough men who require sex or tenderness for a range of reasons. The cliched picture of the abused woman at the hands of violent clients  and predatory pimps simply isn't accurate, they say. Ms Schwarzer has never set foot in a brothel, they like to point out. What does she know?

Foreign Policy