Keritot, Chapter Two, Mishnah Six
1) In the case of all forbidden relations, if one partner was an adult and the other a minor, the minor is exempt;
2) If one is awake and the other asleep, the one asleep is exempt;
3) If one is an inadvertent and the other intentional, the former is liable to a hatat, the latter to karet.
After having delineated several differences between the case of the female slave and other cases of forbidden sex, the mishnah notes that in other ways, most cases of forbidden sexual relations are the same.
Sections 1-2: A minor or one asleep cannot be held responsible for his/her actions, therefore they are exempt.
Section three: This rule is true of most cases prohibited relations (it is not true with regard to female slaves)for inadvertent transgressions, one brings a hatat and for intentional transgressions, one is liable for karet (if done without warning).