AS 18.65.530. Mandatory Arrest For Crimes Involving Domestic Violence, Violation of Protective Orders, and Violation of Conditions of Release.
(b) If a peace officer receives complaints of domestic violence from more than one person arising from the same incident, the officer shall evaluate the conduct of each person to determine who was the principal physical aggressor. If the officer determines that one person was the principal physical aggressor, the other person or persons need not be arrested. In determining whether a person is a principal physical aggressor, the officer shall consider
(1) prior complaints of domestic violence;
(2) the relative severity of the injuries inflicted on each person;
(3) the likelihood of future injury from domestic violence to each person; and
(4) whether one of the persons acted in defense of self or others.