Sexual abuse of a child is generally defined as physical contact or other interaction between a child (under age 17, for example) and an adult when the child is being used for the sexual stimulation or pleasure of the perpetrator or another person. In addition to physical contact, sexual abuse of a child may include (1) the exposure of the genitals of an adult in the presence of a child, (2) the exposure of the genitals of a child, (3) using a child in making pornography, or (4) making a child view sexual acts or pornography.

And in some states multiple instances of sexual contact between an adult and a child may constitute the enhanced criminal offense of continual sexual abuse of a child—which is sometimes a first-degree felony offense.

In Montana, sexual abuse of a child is addressed under various statutes that criminalize sexual assault, sexual intercourse without consent, indecent exposure, and the use of children in pornography. Montana law defines a child as a person under the age of 18 for the purposes of sexual abuse. Sexual abuse can include any form of sexual contact or interaction with a child for the sexual gratification of the adult, exposure of genitals to a child, involving a child in the production of pornography, or forcing a child to view sexual acts or pornography. Montana Code Annotated § 45-5-502 to § 45-5-507 outline the offenses related to sexual abuse, including sexual assault and sexual intercourse without consent, which can be prosecuted as felonies with severe penalties. Additionally, Montana has laws against sexual exploitation of children under § 45-5-625, which includes creating, distributing, or possessing child pornography. While Montana does not have a specific statute for continual sexual abuse of a child, repeated offenses can lead to increased charges and penalties under the state's criminal laws.