It could be, if their behavior constitutes entrapment (which is defined essentially as the police inducing people to commit crimes that they would not otherwise be inclined to commit). A lot of the "entrapment" determination would be based on the amount of cheerleading the police are doing to encourage the criminal behavior, and the predisposition of the people they are communicating with (i.e., whether these people commit the crimes specifically because of the police encouragement, or instead whether they are or would be committing these crimes without that police encouragement).
