Cambodians line up for the start of hearings for former Khmer Rouge foreign affairs minister Ieng Sary.

Jailed Khmer Rouge Ieng Sary was able to participate in a hearing Tuesday, over whether his pardon from a 1979 trial verdict should excuse him from the tribunal. A hearing over his pre-trial detention was cut short Monday, due to health concerns.

Ieng Sary, the regime's former foreign affairs minister, was found guilty of genocide in absentia by a Vietnamese-backed trial following the ouster of the Khmer Rouge, and he was pardoned by King Norodom Sihanouk in 1996.

The hearing continues Wednesday, as tribunal judges seek to decide whether the 1996 pardon would make him ineligible for trial by the Khmer Rouge tribunal.

"Indeed, the trial of 1979 extends to all the criminal activities that Ieng Sary is accused of until now," Ang Udom, Ieng Sary's Cambodian lawyer, told the court Tuesday. "So there is no need to make a trial twice, based on the principle of [double jeopardy]. This principal says that one person cannot be tried twice for the same accusation."

Co-defense laywer Michael Karnavas told the court Tuesday Ieng Sary should be kept under house arrest. On Monday, Ieng Sary's weakened condition prevented the afternoon session of a hearing to determine whether he should be detained ahead of his atrocity crimes trial.

Yeth Chakrya, co-prosecutor, told the court that Ieng Sary was facing crimes other than genocide, and the tribunal had found evidence of crimes against humanity, torture and war crimes. The pre-trial chamber must consider this, he said, and must reject the decision of the 1979 trial.