Kaing Kek Iev, the jailed Khmer Rouge prison chief better known as Duch, told tribunal judges Monday he at least once disobeyed orders from superiors to poison an inmate.
Duch was head of the Tuol Sleng torture center, where prosecutors say he was responsible for the torture and murder of 12,380 people.
Duch said he had ignored orders from Pol Pot’s lieutenant, Nuon Chea, who is also in tribunal detention, to poison at least one prisoner, dispensing pain relief tablets instead.
“The reason was pity, and also to avoid killing the prisoner myself,” he said.
Duch has admitted to responsibility for ordering torture and killing, but he has never admitted to doing any himself.
Now 66, he faces charges of war crimes, crimes against humanity, torture and murder, in the first trial to be undertaken by the UN-backed court.