There was a guy that won his case a few years ago after he went to meet a young gal.. After they arrested him.. yada yada, They said that he had travelled there to meet a minor, and he said, he did not meet a minor.. the only person he met was an adult police officer. Apparently 'intent' wasn't strong enough to hold up. So one sick fuck got away with it.
What that has to do with this topic, I have no idea..
U.S. Customs has the biggest kiddie porn collection in the world.. and you can bet your ass that some of those guys are gettin off on it.
No.. they can't say they are 18, then say they told you they were 16 once you meet in order to bust you. and that wouldn't be entrapment. That would be corruption and as said before.. they have no need to do that.. they are too busy doing it the right way.