What did Israeli military and political leaders know about the Sabra-Shatila massacre and when did they know it? And once they knew of it what they do to stop it?
These are the main questions now being pursued by the three-man Israeli commission of inquiry into the September killing of Palestinian refugees in Beirut.
The political fallout cannot be measured until the results are in. Unlike the televised Watergate hearings in the United States in 1973, much of the testimony is held in private. Even the public hearings, which began Oct. 20, are not televised.
The key will be how the commission members evaluate the degree of negligence in high places and on whom they pin the blame. Then will come the political punch.
Observers here have noted that Defense Minister Ariel Sharon appeared ready to place the burden of responsibility on Army Chief of Staff Rafael Eitan, who testified privately. And Mr. Sharon confirmed Prime Minister Menachem Begin's contention that Mr. Begin did not know about the massacre until Saturday morning , when it ended.
One clue to the outcome of the current hearings is the issues on which the commission has pressed Mr. Sharon and another key military figure, Maj. Gen. Amir Drori, in public - and the contradictions apparent in their testimony. Some the issues are these:
* Why didn't Israeli military officials foresee that vengeful Christian militia-men might massacre Palestinians if they were allowed to enter the refugee camp?
Mr. Sharon was pressed hard on this issue Oct. 25 by Yitzhak Kahan, head of the inquiry and Israeli chief justice, and fellow members Aharon Barak and Yona Efrat.
''Not one of us foresaw - nor could have foreseen - the atrocities committed in the neighborhood of Shabra and Shatila,'' Mr. Sharon insisted. He said Israel had asked Christian forces to enter the camp in order to avoid Israeli casualties in seeking out remaining Palestinian ''terrorists.''
But Mr. Sharon admitted that some civilian killings were expected, and that he did not expect the Christians to abide by Israeli military ethics. Moreover, General Drori, Israel's chief of the northern command, admitted during open testimony on Oct. 31 that ''everyone, somewhere in his mind'' feared that Phalange soldiers might slaughter Palestinian refugees in the camp. (Deputy Prime Minister David Levi also spoke of a possible massacre at a Cabinet meeting on Thursday evening, Sept. 16 - a point raised by Justice Barak.)
General Drori said such reservations were dismissed because the Phalange, though involved as both victim and perpetrator of previous massacres by and of Palestinians, ''has not done this kind of thing'' while fighting alongside Israelis.
Throughout the public testimony, Mr. Sharon and General Drori testified that the Christian fighters who went into the camps were the Lebanese Forces, built around the core of the Phalange militia. Lebanese Forces commander Fady Frem has denied his men had any involvement.
* When did senior Israeli officials know a massacre was taking place?
Defense Minister Sharon said his first inkling came when Israeli Chief of Staff Rafael Eitan found him at 9 p.m., Friday, Sept 17, 27 hours after Christian militiamen had entered the camp, and reported that the Christian ''overdid it.'' General Drori says he first heard of ''irregular actions'' taken by Phalangists late Saturday morning, and a full picture emerged only after reports began filtering in later from foreign medical personnel and from journalists.
But General Drori also testified that he had ordered the Phalangist military action halted 24 hours previously, on the morning of Friday, Sept. 17, because of a ''bad feeling'' about what the Phalangists were doing.
General Drori's testimony on timing was called into question by the commission on Oct. 31 when it released the name and private testimony of Lt. Avi Grabovsky, an assistant tank company commander. He said he saw Phalange militiamen kill five women and children in Shatila early Friday morning from his post at the edge of the camp. His fellow crew members said it already had been reported to the regimental commander, who replied ''We know, its not to our liking'' but said not to intervene.
* Why, after Christian militias had been formally asked on Friday afternoon to stop their operation, were they allowed to remain inside the camp until early Saturday morning?
This is likely to be a key point of questioning. Mr. Sharon insisted that he had believed General Eitan's orders were being carried out and considered this a ''reasonable'' amount of time for a withdrawal by Christian troops. General Drori said there was no sense of urgency since ''we didn't have what had really happened.''
Swee Chai Ang, a surgeon at Gaza Hospital on the edge of the refugee camp, testified Nov. 1 that foreign medical volunteers waited in vain for an expected deluge of casualties. Instead, all day Friday, they heard only the crackle of machine-gun fire in the camp with no answering fire.