But wouldn’t a) putting the burden entirely on the accused be a violation of the presumption of innocence? And b) wouldn’t every “pedophile” just claim that they knew it was an adult that they were setting up a meeting with, and say they thought it was part of the role-play? It’s illegal to fuck children, but it’s not illegal to have your girlfriend pretend to be a child while you fuck her (though it is kinda repugnant).