Jacobson v. United States
United States Supreme Court
503 U.S. 540 (1992)
Jacobson (defendant) ordered adult reading material that turned out to contain photos of young boys, before Congress made mailing child pornography illegal. Over the next two-and-a-half years, two federal agencies used four fake organizations to repeatedly probe his interest in child pornography through questionnaires and materials criticizing censorship. He eventually ordered a magazine depicting boys from a government sting and was arrested on delivery; the only evidence of his interest in child pornography, aside from the initial legal purchase, came from the government's own solicitations. He was convicted after the jury was instructed on entrapment.
Whether entrapment has occurred where a person showed interest in an activity before it became illegal, then engaged in it only after prolonged, repeated government inducement, without independent evidence of predisposition prior to that inducement.