Ten members of the Khmer National Liberation Front (KNLF) charged with “plotting” over a planned protest at the Vietnamese Embassy two years ago appeared in court yesterday, with six requesting leniency after defecting to the ruling CPP.

The men were arrested on October 22 and 23, 2014, with merchandise such as caps and banners that they planned to bring to a protest calling for the Vietnamese to respect the Paris Peace Accords, which put an end to Cambodia’s decades-long civil war in October 1991.

Authorities have not explained how the protest plans constituted “plotting” – a charge defined as “a resolution . . . to commit an attack” that threatens state institutions – and at yesterday’s hearing at the Phnom Penh Municipal Court, defence lawyer Neang Hay called for the charges against the 10 to be dropped as there was no evidence to support them. Mon Vimean Champa, lawyer for Sam Serey, the self-exiled leader of the KNLF, who was being tried for the same charges, made the same argument.

However, Phnom Penh deputy municipal police chief Sim Vuthy, who led the arrests in 2014, testified that he believed the charges were justified because the 10 on trial were named “ministers” in a government-in-exile created in Denmark on October 23 this year.

While four of the accused denied being KNLF members or plotting anything more than a peaceful protest, the six others pleaded for leniency, explaining that Suth Dina – the jailed former ambassador to South Korea who is awaiting trial for corruption – persuaded them in prison to join the ruling party.

“I met Suth Dina, and he explained it to me, and I decided to support the CPP,” said 24-year-old Chhun Chhat, who admitted to being a member of the KNLF. “I strongly deny what Sam Serey said – that we were ministers for something.

“I would like to file a complaint against Sam Serey and [opposition leader] Sam Rainsy for $1 million. I would like to be the surviving witness to . . . explain to the public that the courts are not corrupt.”

Speaking from Denmark, Serey, who has denied claims his group is a terrorist organisation, said he could not fault his members for defecting.

“It is their right, because they want to be released. I have no ability to help them to be released, so it’s their decision,” he said. “The CPP tells them they have to do this if they want to be released.”

However, CPP spokesman Sok Eysan said that it would not help them secure a release.

“When they are in jail, they come and support the CPP. They are clever,” Eysan said, questioning the motivations of the KNLF turncoats. “Why didn’t they join before committing their crimes?”