system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why if prostitution is illegal, hookers do not simply go through a motions of 'borrowing' money upfront and then pretending to want have sex afterwords? 

I know it obvious what they're doing, but it still would technically be within the law. Is there something else I should know?
gpt
The legal loop hole I've seen is to hire the girl as a 'model' for nude photos.

That way there is a legal excuse for a exchange of currency, and you can tell if the girl is an undercover cop if she doesn't agree to the 'photo session' before any talk of sex beings.