@Sarah Buchanan do what you feel is best for the offender and your company. Personally, I respect you for wanting to understand this guy and the specifics of the incident. Shows good character on you and for him to actually volunteer some info. One the flip side, it could tarnish your reputation, but I subscribe to the philosophy of second chances.
@Shiva Bhaskar Their law stipulates 2 things, under the age of 10 = 10 years in prison; between 10-16 yrs old, and actor is 3+ yrs older than victim = 15 years. Not sure why the age disparity makes a difference, unless they are covering for children that are really young that would possibly commit this act. The 3rd Degree label lends me to believe it was not an aggravated assault/rape, yet something that was"consensual". I feel there is more to the story but nothing that would lead me to think he is lying about what has happened.
And I agree with @Dawn Burwell there are some girls that don't act, dress or even look like they are 13.