Illinois Statutes Chapter 720. Criminal Offenses § 5/11-1.70. Defenses with respect to offenses described in Sections 11-1.20 through 11-1.60

(a) It shall be a defense to any offense under Section 11-1.20, 11-1.30, 11-1.40, 11-1.50, or 11-1.60 of this Code where force or threat of force is an element of the offense that the victim consented.

(b) It shall be a defense under subsection (b) and subsection (c) of Section 11-1.50 and subsection (d) of Section 11-1.60 of this Code that the accused reasonably believed the person to be 17 years of age or over.

(c) A person who initially consents to sexual penetration or sexual conduct is not deemed to have consented to any sexual penetration or sexual conduct that occurs after he or she withdraws consent during the course of that sexual penetration or sexual conduct.