The prime minister has selected 14 senior officials – all members of the ruling party – to probe the cold-case murders of three union leaders, including Free Trade Union (FTU) president Chea Vichea, though scepticism remains about the timing and motivation behind the new investigation.

According to the letter signed by the premier on September 15, the special inter-ministerial commission – first announced in June – will be led by Interior Ministry Secretary of State Em Sam An, a high-ranking official and member of the Cambodian People’s Party Central Committee who has previously stood in for Sar Kheng as Interior Minister.

Sam An’s deputies will be Labour Ministry Secretary of State Mam Vannak and Justice Ministry Secretary of State Ngor Sovann.

Vichea was gunned down in Phnom Penh in January 2004, while FTU presidents Ros Sovannareth and Hy Vuthy were shot dead in May 2004 and February 2007, respectively.

Cambodia has long faced international pressure to bring the perpetrators to justice. Two men initially charged with killing Vichea – Sok Sam Ouen and Born Samnang – spent nearly six years behind bars before being acquitted by the Supreme Court in 2013.

Last year, Chan Sophan was cleared of killing Vuthy after spending nine months in prison.

While in the case of Sovannareth’s murder, Thach Saveth was convicted in 2005 then provisionally released in 2011.

Although authorities have made sporadic announcements that the investigations remain open, the cases remain unsolved.

Speaking yesterday, FTU president Chea Mony, brother of Vichea, said he doubted the new task force would deliver a better result, citing suspicions of government complicity in the crime.

Mony alleged people at the ministries of interior and labour knew the identity of the killers but “dare not say”.

“We’ll wait and see whether we get justice,” he said.

Sam An yesterday said he had yet to receive the decision of his appointment and declined to comment further.

The commission will also include Council of Ministers Secretary of State Ngor Hok Ly, National Police Commissioner General Neth Savoeun, military police Commander Sao Sokha, Phnom Penh Governor Pa Socheatvong, Svay Rieng Provincial Governor Chieng Am and Phnom Penh municipal police chief Chuon Sovann.

Also involved are two members of the Council of Minister’s Council of Jurists, Chhit Boravuth and Ly Chantola, Svay Rieng provincial police chief Koeng Khorn and two Foreign Ministry officials: Sun Darin, head of the International Organisation Department and Oeng Vanth, head of the Legal Department.

Bradley Cox, director of the film Who Killed Chea Vichea?, said he doubted the commission would deliver justice for the men’s families.

“Vichea was killed 11 years ago, and the government never showed the slightest interest in finding the real killers.

So why now? What’s to gain? Maybe it’s a bit of theatre for the international community,” he said via email.