OK, I just ran across this thread, and I’m not going to read through all 200+ posts. However, in perusing the last page, it does not appear that anyone has brought up that ignorance of age can be a legal defense. If this has already been covered I apologize.
In Indiana, the offense of a person over 18 having sex with someone who is over 14 but under 16 is called Sexual Misconduct with a Minor. It is covered in I.C. 35-42-4-9.
I have seen one case in my career where I thought this defense should have been raised. Guy is home from college for Christmas break and meets up with some high school friends. They pick him up in a car driven by a girl he doesn’t know. They go to a party where he ends up banging the girl who was driving the car. Turns out she is actually 15 and was driving the car illegally. The girl’s cousins catch them in the act and beat the living shit out of the guy.
Seems to me that he could have made a good case that he reasonably believed she was 16 based on her driving a car. But he was scared to try it because the consequences of losing would have been pretty severe. He got a pretty good plea deal that allowed him to plead to a misdemeanor and kept him from having to register as a sex offender so he took it.