A victim of Pol Pot’s regime, who first began testifying three years ago but refused to continue in fear for his life, is unlikely to return to be cross-examined on fresh testimony he began to offer last month, the Khmer Rouge tribunal heard yesterday.

With parties failing to hash out what to do with civil party Sar Sarin’s partial evidence – which the defence says implicates a senior ruling party official, but is unusable if incomplete – the trial chamber ultimately requested written submissions on the complex legal question.

Sar Sarin, admitted as a civil party in Case 002/01 and Case 002/02 against Nuon Chea and Khieu Samphan, began testifying in 2013 but abruptly stopped, saying he feared repercussions from those still loyal to the Khmer Rouge. Sarin then refused to continue unless, a court document shows, “extensive protective measures were granted to him, namely the provision of a police escort for the remainder of his life”, or asylum for him and his family in another country.

The Witness and Expert Support Unit found that while he had a subjective and “generalised fear about the possibility of reprisals”, they could not see “any tangible or objective basis for these fears”. Further, they reported his return to the court was “unlikely to be conducive to ascertaining the truth or otherwise in the interests of justice”.

But Sarin did return, on November 8 this year, to testify anew in the second phase of the case against Chea and Samphan. However, after being questioned by the prosecution, Sarin refused to re-appear for cross-examination by the defence.

As a civil party – a victim to the regime entitled to moral reparations – Sarin cannot be compelled to appear, as a witness can. When asked why Sarin was put on the stand again, given his history, lead co-lawyer for Civil Parties Marie Guiraud said she was unable to comment.

Victor Koppe, defence lawyer for Nuon Chea, said Sarin was “the first-ever witness to appear in this courtroom who has given evidence of former Lon Nol officials in the East Zone”, and such evidence warranted calling Uk Bun Chhoeun – currently a ruling party senator – to the stand.

However, Koppe said as the defence had no opportunity to probe Sarin on his statements, the evidence he had already given ultimately should be struck from the record.

Samphan defender Anta Guisse also argued the partial evidence was unsuable. Judge Jean-Marc Lavergne, for his part, said Sarin’s behaviour had been “incoherent”.