A controversy over whether the names of victims executed at the notorious Tuol Sleng prison should be inscribed on a stupa has raised questions about how best to commemorate those who died.

Bou Meng and Chum Mey may have spent much of their lives within spitting distance of one another, first as prisoners in Tuol Sleng and then as survivors selling memoirs on the grounds, but the two men couldn’t be more different.

Meng is small and worked as a painter; Mey is taller and stooping with a mop of white hair and was a mechanic. Meng joined the Khmer Rouge as a guerrilla fighter in 1970; Mey didn’t. What they had in common was surviving the torture chamber that killed some 14,000 people.

Friendly for years, they had a falling out over the passing of a law criminalising genocide denial in Cambodia last year. When a debate erupted in recent weeks over the construction of a new memorial stupa at Tuol Sleng, they again took opposing points of view.

Public ceremonies are held twice a year at the former prison – once over Pchum Ben and once to celebrate the May 20 day of remembrance – and a stupa that would replace one destroyed by a storm in 2008 was deemed a suitable place to hold them.

The monument, planned by the Victims Support Section of the Extraordinary Chambers in the Courts of Cambodia (ECCC) and the Ministry of Culture and Fine Arts, is set to be inaugurated early next year.

While the stupa has been widely welcomed, the proposal to inscribe names of victims has met with passionate resistance from academics and Khmer Rouge survivors who say that it risks offending families if the names of cadres are listed.

Marcos Smith, coordinator of the Civil Peace Service Program of German government aid agency GIZ, which is funding the $87,000 project, said they planned to list the names on the stupa or else in a book displayed nearby, but details had not been discussed.

Representatives from the ministry and the ECCC, which sentenced Tuol Sleng head Duch to life in prison in 2012, said they were this week finalising a memorandum of understanding on the issue.

Of the men, women and children killed at Tuol Sleng, also known as S-21, some 70 per cent were Khmer Rouge cadres rounded up during a frenzy of internal purges.

“In no country in the world do they take the names of someone who kills and put it on a stupa,” said Mey, sitting on a bench shaded by the wide branches of a plumeria tree at Tuol Sleng earlier this week.

He has visited Hiroshima in Japan and Holocaust memorials in Germany and it was he who first proposed the stupa to the ECCC in July 2010. Initially he agreed with the inscription.

“Who’s the cadre and who’s the victim? We’re all human beings,” said Mey, who is the president of the Victims Association of Democratic Kampuchea.

“It’s important for the young generation to know that this was a high school and it became a prison – it’s important for them to stop this history happening again,” he added.

But after reflection and consultation with the Documentation Center of Cambodia (DC-Cam), he came to oppose the idea, believing that relatives of victims might be upset reading the names of Khmer Rouge cadres along with their family members. His own wife and children were killed.

But Bou Meng, the deputy president of the Victims Association of Democratic Kampuchea, said he would regret if the names were not inscribed.

“I feel disappointed because they just eliminate the names of the victims,” he said.

The distinction between victim and perpetrator can be blurry when it comes to the regime, said Sirik Savina, director of the Museum of Memory Project at DC-Cam.

“Even though there is still a grey area in defining former Khmer Rouge members as victims or perpetrators, it is worth taking historical facts into consideration when we attempt to inscribe names of the victims,” she wrote in an email.

“If you look at the documents at Tuol Sleng such as confessions or biographies you can trace their background which can help you identify which of them had served the Khmer Rouge.”

While including them could be offensive, leaving out Khmer Rouge cadres but naming others could also raise problems.

Youk Chhang, the director of DC-Cam, said: “Even though the same person who committed a crime does good later, that does not mean that the crime they have committed can turn them into a victim,” he said.

“At the same time, not all Khmer Rouge are bad people.”

The inscription of names is not a traditional form of Cambodian memorial, he added.

Farino So, head of the Cham Oral History Project at DC-Cam, said a list may alienate the Cham Muslim community, more than 40 of whom were imprisoned in Tuol Sleng.

“While stupa erection can be justifiable because it is a Cambodian practice, name inscription raises some concerns: Western practice, incompatibility with Islamic traditions, and problems with inclusion and exclusion,” So wrote in an email.

“All of which raises a main question: is it an appropriate form of reparation that would help victims rest in peace and survivors find solace?”

Solace and the means of finding it are clearly subjective.

To the two tourists who watched this week as Chum Mey sat cross-legged in the place he was tortured and placed a metal bar over his feet to re-enact the horrors done to him, solace might have seemed elusive.

But the survivor said confronting the place has helped him come to terms with the horror that happened there.

“Four or five years ago, when tourists came and asked about my experience in the past, I always cried with them.

“But later on I came here too often, and the ECCC found justice for me, so it feels OK to come here again.”