The court, known as the Extraordinary Chambers in the Courts of Cambodia (ECCC), will deliver its verdict on an appeal by Khieu Samphan, 91, on Thursday morning. Khieu Samphan, who was a former head of state, was found guilty of genocide against Vietnamese in 2018. An estimated 1.7 million people were killed under the Khmer Rouge through a combination of mass executions, starvation and labor camps, in one of the worst atrocities of the 20th century. By the time the regime was overthrown in 1979, about 25% of Cambodia’s population had died. An estimated 20,000 ethnic Vietnamese, as well as 100,000 to 500,000 Cham Muslims, were among the dead. The court, which will now complete its work, has provided a space for national healing and justice, but has also been criticized for its slowness, cost and vulnerability to interference by Hun Sen’s government. The tribunal, which was established in 1997 and includes both Cambodian and international judges, has cost more than $330 million. It led to three convictions, including Khieu Samphan, Nuon Chea, who was second in command to Pol Pot, and Kaing Guek Eav, known as Comrade Duch, who headed the notorious S-21 prison. The main perpetrators have died before they could face justice, including “Brother Number One” Pol Pot, who died in 1998. Khieu Samphan was sentenced to life in prison for genocide and other crimes in 2018 along with Nuon Chea. The ruling at the time emphasized that Khieu Samphan “encouraged, instigated and legitimized” criminal policies leading to civilian deaths “on a massive scale,” including the millions forced into labor camps to build dams and bridges and the mass extermination of Vietnamese . Buddhist monks were forcibly expelled while Muslims were forced to eat pork. The pair were already serving life sentences for crimes against humanity over the forced evacuation of Phnom Penh in April 1975, when the city’s residents were taken to rural labor camps where they faced hard work, starvation and disease. Nuon Chea died in 2019. Khieu Samphan’s lawyers accused the court of taking a “selective approach” to testimony and using legal criteria he could not have known when the alleged crimes took place more than 40 years ago. Kaing Guek Eav, who ran the S-21 prison where an estimated 18,000 people were tortured and murdered, was sentenced to 35 years in prison in 2010. He died in 2020. AFP contributed to this report