A person generally commits the criminal offense of sexual assault of a child—regardless of whether the person knows the age of the child at the time of the offense—if the person (1) causes the penetration of the anus or sexual organ of a child by any means; (2) causes the penetration of the mouth of a child by the sexual organ of the person; (3) causes the sexual organ of the child to contact or penetrate the mouth, anus, or sexual organ of the person or another person; (4) causes the anus of a child to contact the mouth, anus, or sexual organ of the person or another person; or (5) causes the mouth of a child to contact the anus or sexual organ of the person or another person.

The naming and definition of the criminal offense of sexual assault of a child varies from state to state. These criminal offenses are generally located in a state’s statutes—often in the penal or criminal code.

In Minnesota, the criminal offense of sexual assault of a child is referred to as 'criminal sexual conduct' and is codified under Minnesota Statutes, specifically sections 609.342 to 609.3451. These statutes define various degrees of criminal sexual conduct, with the first degree being the most severe. The acts described in the topic, involving penetration or contact between a child's sexual organs and those of an adult, or any other form of sexual contact, would typically fall under first or second-degree criminal sexual conduct, depending on the specific circumstances. Minnesota law does not require the perpetrator to have knowledge of the child's age to be charged with this offense. The severity of the charge and the resulting penalties, which can include lengthy prison sentences and registration as a sex offender, are determined by factors such as the use of force or coercion, the age of the child, the age difference between the offender and the child, and whether the offender held a position of authority over the child.