I don't know anything about universal jurisdiction. I was in GA when I was in the age range where I would have been affected and like Trig was saying, there are usually other laws where say 2 underage people could have sex if they were both underage. What I found weird about it is you could have a 17 year old guy with a 15 year old girlfriend legally having sex but the day he turns 18 it's illegal. BUT... I never saw any of these laws used/enforced unless it was a rape case or angry parents. Miley Cyrus blabbered her mouth about having a 20 year old boyfriend when she was 15 and I don't think anyone did shit about it.