RI Gen L § 12-29-3 (2020)
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(c)(1) When more than one family or household member involved in a domestic violence incident states a complaint, the officer shall investigate each complaint to determine whether there is probable cause to believe a crime has been committed. The officer shall not dismiss the incident by presuming two-party (2) guilt.
(2) When the officer has probable cause to believe that family or household members have assaulted each other, the officer is not required to arrest both persons. The officer shall arrest the person whom the officer believes to be the primary physical aggressor.
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