How do you check if a prostitute is a cop?

There is no reliable method. An undercover officer never has to admit it while undercover.

It may also be that you are seeing a real prostitute who was recently arrested and has agreed to work with the police to reduce their own charges. Best answer above is not totally right. first if a cop is a prostitute you can tell because the cop prostitute will ask you about prices, when a real one will just want to get to it to get so she can get more sales.