In any prosecution under this chapter in which the victim's lack of consent is based solely on his incapacity to consent because he was less than sixteen (16) years old, an individual with an intellectual disability, mentally incapacitated, or physically helpless, the defendant may prove in exculpation that at the time he engaged in the conduct constituting the offense he did not know of the facts or conditions responsible for such incapacity to consent.
KRS 510.030