The romeo and juliet limit is only three years... this is criminal.
I've found sources that mention 4 years.
ETA:
5-14-127. A person commits sexual assault in the fourth degree if the person: (a)
(1) Being twenty (20) years of age or older, engages in sexual intercourse or deviate sexual activity with another person who is:
(A) Less than sixteen (16) years of age; and (B) Not the person's spouse; or
(2) Engages in sexual intercourse with another person who is:
(A) Less than sixteen (16) years of age; and (B) Not the person's spouse.
(b)
(1) Sexual assault in the fourth degree under subdivision (a)(1) of this section is a Class D felony.
(2) Sexual assault in the fourth degree under subdivision (a)(2) of this section is a Class A misdemeanor if the person engages only in sexual intercourse with another person as described in subdivision (a)(2) of this section.