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 Delaware, the criminal offense of sexual assault of a child is addressed under the state's sexual offense statutes, which are part of the Delaware Code. Specifically, these actions are categorized under 'Rape' and 'Unlawful Sexual Contact' among other related offenses. Delaware law defines various degrees of rape, with the first degree being the most severe, and often involves victims who are minors. The law does not require the perpetrator to know the age of the child for the act to be considered a criminal offense. The statutes outline that any sexual penetration or contact with a minor, as described in the provided scenarios, can lead to serious felony charges. The severity of the charges and the associated penalties, including imprisonment, fines, and registration as a sex offender, depend on the specific circumstances of the offense, such as the age of the child, the use of force or threat, and the age difference between the perpetrator and the child. It is important for individuals to be aware of these laws and the severe consequences of engaging in sexual conduct with minors.