For roughly the cost of buying a pornographic DVD -- on sale -- you can purchase sex in London; for the cost of a hot new X-rated release, you can purchase high-risk sex, like unprotected anal intercourse.

That's according to a new report, which surveyed 921 brothels in the city and found that "full sex" costs as little as 15 pounds (about $26) and unprotected sex just 10 pounds more. Sex with a prostitute on average costs 62 pounds (just over $110) and goes for as much as 250 ($442). Researchers found women of 77 different ethnicities working in the city's brothels, although many were from eastern Europe and Southeast Asia -- both of which are known for sex trafficking.

The report bolsters Britain's fight against sex trafficking and, notably, Minister for Women Harriet Harman's campaign to criminalize the sale of sex. On Thursday, in the wake of the report's release, Harman visited with trafficked women, underscored another recent survey finding that most Brits support criminalizing johns and railed against the "multimedia misrepresentations of commercial sex as a glamorous, easy and fun career choice for girls." She added: "For most women involved in prostitution, the reality is a cycle of violence and coercion, perpetuated by poverty and inequality."

Still, I remain unconvinced that outlawing prostitution is the best approach to reducing sex trafficking or that it will better protect the workers. Last year, British Liberal Democrat David Howarth very reasonably looked at the actual effect of criminalizing sex work: "Evidence from Sweden in making prostitution illegal has shown that it doesn't help in reducing human trafficking. It, in fact, increases violence against women and makes the practice of prostitution far more risky for all involved."