Research about interpartner agreement on intimate partner violence (IPV) is mainly based on community and clinical samples, with forensic or court-related samples being overlooked. This study assesses interpartner agreement on IPV reports based on the Revised Conflict Tactic Scales, aiming to explore if the proxy method would be reliable in a court-related setting. The study sample comprised 62 different-sex couples identified in the Portuguese judicial system due to an IPV-related crime perpetrated by men. Agreement was assessed based on different indexes: percent agreement and Gwet’s AC1 for occurrence, and Tau-b and intraclass correlations for frequency. Men’s and women’s perpetration were considered. Results showed that interpartner agreement on IPV occurrence (ranging from poor-to-very good) tended to be higher and more consistent among indexes than agreement on IPV frequency (ranging from non-existent to strong). This study highlights the need to collect both partners’ reports in court-related settings.