Sex trafficking is difficult to prove and the police now hope to be able to target the rogue parlours by studying their finances, according to a report in the Dagens Nyheter (DN) daily.
Raids on several salons in the Stockholm area revealed serious mismanagement of cash.
There are currently almost 190 Thai massage salons in Stockholm.
“We have clear indications both in the trafficking of girls and that many deal with black money and pay unreasonably low payroll taxes,” said Conny Svensson at the Tax Agency (Skatteverket) to the newspaper.
In Stockholm, the number of massage parlours in operation has doubled since 1990.
The police are convinced that some of them sell sexual services, including massage that ends with masturbation, but can not prove their suspicions.
“We also hear of and witness other, more advanced sexual services, which means that you may soon wonder if we have a brothel on every or every other street corner,” said Ewa Carlenfors, head of the section against trafficking at Stockholm police, to DN.
“But it is very difficult for us to prove in court the customers on whom a sexual act was performed.”