In a 14-page memo, Kasper-Ansermet said Cambodian staff followed the instructions of his Cambodian counterpart, You Bunleng, only.
Duch said Wednesday that Pol Pot and Nuon Chea “monopolized” decisions on “policy, commerce, the economy and the military.”
Kasper-Ansermet’s resignation throws further doubt of moving forward with a group of additional prosecutions known as cases 003 and 004.
During testimony Tuesday, Duch admitted he was “not clear” on the policymaking of the regime.
Duch tells the UN-backed court that the regime had a policy to “arrest and kill” perceived enemies and spies.
Duch is scheduled to testify at the court on Monday in the atrocity crimes trial of Nuon Chea, Khieu Samphan and Ieng Sary.
Cambodian prosecutors presented a list of experts to the Trial Chamber of the court who could affirm the authenticity of the documents.
Defense lawyers for Nuon Chea and Ieng Sary also objected to prosecution documents on Tuesday.
The classes are attended mainly by foreign tourists and held in the group’s former torture center.
Kaing Kek Iev, better known as Duch, is set to testify on March 20 in the case against leaders Nuon Chea, Khieu Samphan and Ieng Sary.
In a phone interview, Ellis told VOA Khmer the court’s credibility is failing and that more international support is needed.
An investigation team read the notification order to Im Chaem at her home in Uddor Meanchey province on February 28.