In criminal law, a person is entrapped when he is induced or persuaded by law enforcement officers or their agents to commit a crime that he had no previous intent to commit.
In a court of law, claiming entrapment may be used in defense. In most places, however, the defense of entrapment does not apply if it can be shown that the person accused of the crime would have been likely to commit a similar crime at some point in the future. The mere fact that a law-enforcement officer encouraged a person to commit a crime is usually not enough to prove entrapment.
This makes the use of an entrapment defense difficult for pedophiles, especially if the alleged crime was committed using the resources of a forum or web site devoted to pedophilia. In such an instance, the person's propensity for visiting such web sites could be used to suggest that he also had a propensity to commit crimes against children, thereby nullifying any entrapment defense.
In the minor-attracted community, entrapment may take the form of a law-enforcement officer or a vigilante posing as a boy and inviting the victim to perform some criminal act. Such acts may include sexual chat, trading child pornography, or meeting the fake minor in real life. (In some jurisdictions, such as the UK, meeting a minor may be illegal under certain conditions.)