At least they've stopped trying to come up with answers about pedophilia by using 100% prison inmates as test subjects. That was the craziest thing I've ever heard.
My mind fails me, but somewhere I heard the last "real" study of pedos in the US was in 1970, in which the researcher got some sort of official guarantee from the US government not to go after his research subjects for criminal behavior. This meant his pool of test subjects could freely tell him whatever info he wanted while knowing they would not be charged criminally as a result. This opens up an entire new world of understanding about this topic, which I am sure is exactly why this guarantee has not been issued again to any researcher for nearly 50 years. It's sort of insane to claim you want to stop something without fully understanding it, yet not allowing the freedom of researchers to ask subjects what they want to know without those people fearing legal retribution for sharing with the researcher what he asks.