Are you this naive? He RESIGNED.
This has nothing to do with being naive. Resignation does not equal admitting guilt to any illegal or immoral act. It's entirely possible that people with huge imaginations and dubious political motives have turned this into something that looks bad, even when it's not, and yes, considering the guy was an anti-porn advocate, I could see that being enough for a resignation.
I refuse to condemn this man until I know more details.