Colorado Revised Statutes Title 18. Criminal Code § 18-6-803.6. Duties of peace officers and prosecuting agencies–preservation of evidence
(2) If a peace officer receives complaints of domestic violence from two or more opposing persons, the officer shall evaluate each complaint separately to determine if a crime has been committed by one or more persons. In determining whether a crime has been committed by one or more persons, the officer shall consider the following:
(a) Any prior complaints of domestic violence;
(b) The relative severity of the injuries inflicted on each person;
(c) The likelihood of future injury to each person; and
(d) The possibility that one of the persons acted in self-defense.