(a) An offender commits the crime of sexual abuse of a minor in the fourth degree if (1) being under 16 years of age, the offender engages in sexual contact with a person who is under 13 years of age and at least three years younger than the offender; or
(2) being 18 years of age or older, the offender engages in sexual contact with a person who is 16 or 17 years of age and at least three years younger than the offender, and the offender occupies a position of authority in relation to the victim.
(b) Sexual abuse of a minor in the fourth degree is a class A misdemeanor.