It seems to me that although Napolitano is citing entrapment in his exchange with O'Reilly, it seemed to me by his answers and arguments that he's erroneously conflating the legal defences of 'entrapment' with 'impossibility.' Impossibility defense - Wikipedia, the free encyclopedia Factual impossibility was not traditionally accepted at common law whilst legal impossibility was and remains so today but in a much more restrictive manner. Legal impossibility - Wikipedia, the free encyclopedia For example, if a person decides to fish in a pond believing that fishing is prohibited there but it actually is permitted, that is full legal impossibility because the act itself is not a crime, even though the person had the bad intentions to violate such a prohibition believing it existed when he/she did it. But, to use an classic example from the movie A Few Good Men: Kaffee: It was oregano, Dave, it was a dime bag of oregano. Lieutenant Dave Spradling: Yeah, well, your client thought it was marijuana. Kaffee: My client's a moron, that's not against the law. . . . that's no longer an accepted impossibility defence in most if not all American jurisdictions now thanks to adoptions of the Model Penal Code and other statutory or court abolitions of that application of the defence. Today a pothead who buys a dime bag of oregano believing it was pot is guilty of attempted purchase of marijuana so long as the action being sought is illegal. The wiki explanation is even a bit inaccurate because if, for example, cops set up a 'sting' operation for stolen goods, that's really 'hybrid legal impossibility' at play and it's no longer an accepted defence to claim that the good were in fact not really stolen. It's the same with other kinds of 'stings' like with the kind on To Catch a Predator where the actors and/or cops are posing as minors but they are really over the legal age. Since prosecutions don't bother to charge people with attempts for things that aren't actually crimes, it's pretty much a defence that nobody sees in court anymore because you can't argue the rest anymore insofar as the oregano purchasing pothead, etc.