In this picture taken recently, the paper on the left carries the insurer's signature and is sealed by the police station of the Republic of China, the prevailing administration between 1912 and 1949; while on the right piece, the applicant fills the blanks with her name, nationality, age, address and justification for wanting to become a prostitute, as well as proof of having volunteered to do so. A black-and-white photo of the prostitute-to-be is also pasted under the characters "from Tianjin police station to Tianjin city government". [Xinhua]
To me, it t shows prositutes were legalized, and basically the prositutes were recruited on a volountary basis.
via Liberal Japan