Silent black-and-white scenes, purported to be of Pol Pot’s visit to an East Zone rubber plantation in 1978, opened the Khmer Rouge tribunal hearing yesterday.

Defence lawyer Victor Koppe requested the short clip – featuring a fist-raising crowd and smiling cadre – be replayed for witness Meas Sourn, after he appeared to become “emotional” after viewing it the day before.

The footage, the defence claimed, “clearly” depicted a young Heng Samrin, a former Khmer Rouge official and current president of the National Assembly, months before he defected to the Vietnamese.

Sourn, however, said the face looked like his father, prompting heated debate in the court room. His father, Chan, was the former deputy of the East Zone under Sao Phim, who was accused of plotting a coup d’état.

Statements from other current members of the ruling party, such as Uk Bun Chhoeun, were also drawn upon to question Sourn as to what he knew of competing loyalties among the leadership, a key element of the Chea defence.

Bun Chhoeun’s statement claimed Sourn’s father Chan was “faithful to Pol Pot to the end”, but according to an interview of Heng Samrin by academic Ben Keirnan, Chan was “initially loyal”, but later distrusted.

Sourn said he “did not have a full grasp of the situation” when asked about details of infighting. “After 25 May 1978, not only Heng Samrin’s forces but also other forces were fleeing and fighting against the forces from the centre in the East Zone.”

The trial resumes July 26.