As lawmakers yesterday paid their respects and chose a successor to former Senate president Chea Sim, who died on Monday, Human Rights Watch (HRW) called for renewed efforts to try former Khmer Rouge leaders, saying it was “a mockery of justice” that the 82-year-old had avoided prosecution for “serious crimes”.

In a statement released less than a day after the death of the Cambodian People’s Party president and former Khmer Rouge cadre, HRW accused Sim of “serious international crimes” during the Khmer Rouge years and alleged “possible genocide” and “crimes against humanity” were committed by Sim while he was secretary of Ponhea Krek district in Democratic Kampuchea’s Eastern Zone.

“Chea Sim’s passing is a reminder that virtually all former Khmer Rouge officials have gone unpunished for the millions of deaths and incredible suffering of ordinary Cambodians during Khmer Rouge rule,” HRW Asia director Brad Adams said.

“It is a mockery of justice that Chea Sim could serve in the post-Khmer Rouge Cambodian leadership for decades without ever facing an investigation, much less arrest or prosecution.”

According to 2005 HRW research, which was passed to the Khmer Rouge tribunal in 2006, Sim oversaw a security centre in the region and exercised authority over commune militia who arrested, tortured, killed and “enslaved” the population.

Among those targeted, says HRW, were former Lon Nol regime officials, members of Cambodia’s pre-revolutionary upper classes, fellow Khmer Rouge cadre suspected of political dissent and members of the Vietnamese, Cham and Chinese ethnic groups.

HRW blamed political control exercised over the Extraordinary Chambers in the Courts of Cambodia (ECCC) by Hun Sen, also a former Khmer Rouge cadre, for the evidence against Sim not being seriously pursued.

They added that the prime minister’s influence had “stymied” the prosecution of other former cadres in who held similar positions of responsibility as Sim.

So far only three former Khmer Rouge leaders have been convicted for crimes during the Democratic Kampuchea regime including S-21 jailer Kaing Guek Eav, alias Duch, “Brother Number Two” Nuon Chea and head of state Khieu Samphan.

Hun Sen has long rejected calls to increase the scope of the Khmer Rouge tribunal, suggesting that it could trigger a civil war.

President of the National Assembly Heng Samrin attends Chea Sim’s funeral in Phnom Penh. Heng Chivoan

Sim, together with National Assembly President Heng Samrin, was among six senior government officials who ignored summonses to give evidence in the court’s Case 002/01.

Speaking yesterday, Documentation Centre of Cambodia director Youk Chhang said the allegations against Sim were not new and the decision of the ECCC had to be respected.

“What he did is no secret, it’s been published by scholars in the ’80s. We have to respect the judge’s decision and also expect the judge to follow the rules on the evidence they are holding,” he said.

HRW’s Adams also took aim at Sim’s legacy in law enforcement.

As a member of the Vietnamese-installed government in the 1980s, Sim helped establish a security apparatus which brutally repressed opposition, extracted confessions from torture and sometimes held prisoners indefinitely, often in “dark cells” that were isolated from the world, according to HRW.

“Chea Sim was best known among Cambodians for running the police state in the 1980s that imprisoned and tortured people for peaceful political activities,” Adams said.

“His legacy continues to this day, with unreformed security forces run for the interests of the ruling party instead of the public good.”

Meanwhile, at the Senate yesterday, 52 of 61 senators voted the CPP’s Say Chhum, former Senate deputy, to replace Sim as head of the body, with Nay Pana voted as his deputy.

Although Hun Sen announced in April that he would take over from Sim as CPP president, party spokesman Sok Ey San yesterday declined to reveal when the standing committee would officially appoint a successor.