Proof of an unwritten understanding will suffice. They can, however, give somebody an opportunity to enter into an existing conspiracy where the police agent is a feigned accomplice. The defenses of impossibility and abandonment are of no use in conspiracy law as they are considered the same as no defense. However, some jurisdictions will permit abandonment, but the standard is high, the defendant has to show their complete and total withdrawal by notifying the authorities about their own involvement and taking steps to thwart the conspiracy. Conspiracy doesn't recognize anything sacrosanct about the husband-wife relationship, and a corporation can also be charged as a person with conspiracy if more than one corporation is involved.
Solicitation occurs when the solicitation is made .
Another way of saying this is that the crime of solicitation is over with the asking . It also doesn't matter if it's a crowd or an individual being solicited, and it's even possible to perpetrate solicitation through an intermediary. At common law, these would be crimes that breach the peace or obstruct justice. This list is sometimes called the list of proper utterances for the crime of solicitation. Impossibility of any type is the same as no defense.