Under MCA § 45-5-206(2), partners are spouses, former spouses, persons who have a child in common, and persons who have been or are currently in a dating or ongoing intimate relationship. Family members are mothers, fathers, children, brothers, sisters, and other past or present family members of a household, including step-relations, in-laws, and adoptive relatives. If the other person does not fit one of those definitions, the offense is not partner or family member assault. This page is part of our Montana Domestic Violence Guide.
Why the Definition Matters
The relationship is an element of the offense, which means the State must prove it like any other fact. It also decides which set of consequences applies. PFMA carries minimum jail terms, a required counseling program, and repeat-offense penalties that ordinary assault does not. Our comparison of PFMA and misdemeanor assault sets them side by side.
The same definitions reach beyond the PFMA statute. Subsection (2) says they apply to the warrantless arrest statute (§ 46-6-311), to the offender counseling provisions, and to Title 40, chapter 15, which governs orders of protection.
The Four Kinds of Partner
- Spouses. People who are currently married to each other, including while a divorce is pending.
- Former spouses. The definition has no cutoff based on how long ago the marriage ended.
- Persons who have a child in common. Marriage or a dating history is not required.
- Persons who have been or are currently in a dating or ongoing intimate relationship. This covers current and past relationships. The wording does not refer to the sex of either person and does not require that the couple lived together.
The statute does not define "dating" or say how serious or how long a relationship must be. That gap is where most disputes about this element happen. See PFMA in dating relationships.
Who Is a Family Member
The family definition starts with five named relationships: mothers, fathers, children, brothers, and sisters. It then adds "other past or present family members of a household." Two sentences widen it further:
- Relationships created by adoption and remarriage are included, and the statute gives examples: stepchildren, stepparents, in-laws, and adoptive children and parents.
- The relationships continue regardless of the ages of the parties and whether they reside in the same household.
So an adult son and his father, two grown sisters who live in different towns, and a stepparent and stepchild are all family members under this statute. See PFMA against a parent, sibling, or child.
The Definitions at a Glance
| Relationship | Category | Basis in § 45-5-206(2) |
|---|---|---|
| Current spouse | Partner | Named: "spouses" |
| Former spouse | Partner | Named: "former spouses" |
| Other parent of your child | Partner | Named: "persons who have a child in common" |
| Current or former dating partner | Partner | Named: persons who "have been or are currently in a dating or ongoing intimate relationship" |
| Parent, child, brother, sister | Family member | Named, regardless of age or shared residence |
| Stepparent, stepchild, in-law, adoptive relative | Family member | Named as relationships created by adoption and remarriage |
| Other relative of the household, past or present | Family member | Covered by "other past or present family members of a household" |
| Roommate with no family or dating tie | Not listed | The statute does not name people who only share housing |
Who Is Not Listed
The statute reaches partners and family members. It does not say "household members" or "people who live together." The phrase "family members of a household" still requires a family tie. Reading the text as written, these relationships are not named:
- Roommates or housemates with no family or dating relationship.
- Friends, coworkers, neighbors, and landlords.
- A person your relative is dating, unless some other listed relationship applies.
That is our reading of the definition, and close cases exist. Relatives outside the named list, such as cousins, grandparents, or an aunt, fall under "other past or present family members of a household," and the statute does not spell out what connection to a household is needed. How that phrase applies to a particular family is a question for the court on the facts.
Not fitting the PFMA definition does not make conduct legal. The same act can be charged as assault under MCA § 45-5-201 or as a more serious offense.
How the Relationship Is Proved
In most cases the relationship is not disputed. A marriage, a shared child, or a parent and child relationship is easy to establish through testimony or records. Dating relationships and extended family ties take more: what each person said to officers, messages, photographs, and what witnesses know about the two people.
When the relationship is genuinely in doubt, it becomes a defense issue, covered in not a partner or family member. Whether it is worth raising depends on the alternative charge the State could bring and on the rest of the evidence. That is a judgment to make with a lawyer who has read the file. A&M Law defends these charges in Western Montana: see our PFMA defense page.
This page explains Montana law in general as of the 2025 Montana Code Annotated. It is not legal advice about your specific case.