Ieng Thirith will be remanded to detention and undergo medical treatment to improve her mental abilities, in the anticipation she will one day stand trial, the Khmer Rouge tribunal’s court of final appeal decided yesterday.

The Supreme Court Chamber decided to grant the co-prosecutors’ immediate appeal against the Trial Chamber’s decision last month to unconditionally release Ieng Thirith as she was unfit to stand trial.

In a sharp criticism of the Trial Chamber’s “sweeping conclusion”, errors of law and delegation of responsibilities to the co-prosecutors, the judges of the Supreme Court decided in a vote of 6-1 that Ieng Thirith should continue medical treatment and be re-examined in six months’ time.

“A parallel objective [to ensuring the accused’s presence at trial] is to foster the improvement of the mental health of the accused,” the judges wrote.

One of the experts who examined Ieng Thirith, New Zealand geriatrician John Campbell, suggested a trial of the drug Donepezil, which has a 33 per cent effectiveness rate, to improve Ieng Thirith’s cognitive function.

One in three was a probability that, “from the point of view of the various interests in trying the case, should not be dismissed”, the Supreme Court Judges said.

The former-Khmer Rouge Minister for Social Action was found unfit to stand trial by the Trial Chamber on November 17, two working days before opening statements in the landmark Case 002 began at the tribunal.

Ieng Thirith’s defence counsel first raised queries about her mental abilities in February this year.

New Zealand geriatrician Campbell examined Ieng Thirith in June and concluded she had a “moderately severe dementing illness, most probably Alzheimer’s disease” and recommended her doctors reduce her medication in order to better examine her mental abilities. The Trial Chamber found that while there was a possibility that Ieng Thirith could attempt to feign cognitive impairment, it was considered unlikely that Ieng Thirith could falsely present with dementia.

International Co-Prosecutor Andrew Cayley said his office was “very satisified that the Supreme Court Chamber recognised the strong public interest that the matter be pursued”.

Defence counsel for Ieng Thirith declined to comment on the decision.