 Both raised the entrapment defense, arguing that while they would have made and sold meth regardless of Shapiro's involvement, his supplying of an ingredient that, while legal, was difficult to get due to the bureau's own efforts to dissuade chemical companies from selling it and requiring that those who did sell only to buyers with a valid manufacturer's license, constituted entrapment as a matter of law.In "Sorrells v. United States", , the case where it had first recognized entrapment as a valid defense, and "Sherman v. United States", , another entrapment case involving an undercover drug investigation, the Court had chosen to ground entrapment in the question of whether it could be established that the defendant had a "predisposition" to commit the crime absent government involvement.This has become known as the "subjective" test of entrapment since it involves evaluating the defendant's state of mind.