quote "Jessalyn" :
Stings? What happens in a sting exactly?
This is a situation in which LE poses as either a provider or a client in order to lure the other and arrest them.
There are practical and legal limits (and "moral" ones too) to how far they can go. Cases have been thrown out of court because the officers actually had sex with the ladies before arresting them; understandably, this did not go over very well with the public--"You're using our tax money to get laid?", etc.
Usually, a claim of "entrapment," in which it can be argued that a crime would not have taken place at all without LE activity, is a valid defence.
It is important to keep in mind, however, that in most jurisdictions, officers are allowed to lie in order to lure people. You cannot trust that a person is not a cop by simply asking them, "Are you a cop?", or even the more strict, "Are you in any way affiliated with any law enforcement agency?" They can and do lie, and it usually holds up in court.
Where prostitution is illegal, people can usually be arrested for merely *agreeing* to engage in a sex act for money, so many providers are very careful not to discuss details of what will happen on a date, especially over the phone.
[Note: In all discussions of laws and legality, it is important to take into account the jurisdiction involved, as laws differ, sometimes radically, from country to country and state/province to state/province.]
