Thursday is a somber anniversary, marking 50 years since the fall of Phnom Penh to the Khmer Rouge and the start of a regime that caused one in four Cambodians to lose their lives in just three years, eight months and 20 days — the length of Pol Pot’s reign of terror.

This date is also a chance to reflect on the importance of holding perpetrators to account, providing for survivors and strengthening a rules-based international order.

The Khmer Rouge Tribunal, established in 2006 to try those responsible for the regime’s crimes and whose proceedings ended in 2022, was strongly supported by Japan — a backer of other international justice mechanisms and the rule of law more broadly.