As it emerged that Palestinians might have to wait up to seven months for a ruling, Dr Olivier Ribbelink, the head of research at the Netherland's prestigious TMC Asser Institute warned that some of the 15 judges might use the time to avoid addressing contentious legal areas.
"The problem is we do not know whether they will deal with all the issues involved," he said. "It may be that they will look for arguments not to deal with specific problems."
"There is no doubt that if they go into the issues, they will have to say that it is illegal to build the wall into Palestinian territory and cut off Palestinian villages."
"If their decision goes the other way, the position of the court will be damaged in the eyes of large parts of the world," Ribbelink told Aljazeera.net
Peter Bekker, senior counsel for the official Palestinian delegation, declared himself "very pleased" with the way proceedings were going, but he shared some of Ribbelink's fears.
"We do have concerns that the judges' opinion might be general and vague," he told Aljazeera.net. "But overall we are still confident that they will produce a well reasoned and helpful position that will give clear guidance on the matters that the General Assembly has requested an opinion on."
"The court has never ruled against a request for an advisory opinion from the UN General Assembly before. Based on history we should be looking forward to this one."
'Right to defend'
Israel contends that the UN General Assembly resolution of 21 October referring the matter to the international court was only a recommendation - and so any ruling by the court is not binding.
Palestinians say wall disrupts life
and grabs parts of their land
Their position is that the construction of the wall is a political dispute to be settled in negotiations and that in the meantime, Israel has the right to defend itself.
The US and European Union support this interpretation of the law but the legal problem with their argument is that the wall being constructed does not follow the 1967 Green Line, the internationally recognised eastern border of Israel.
"No-one doubts that the state of Israel has the right to self-defence," Ribbelink said. "The issue is to what extent? What does that mean? How far can you go? What are the limits, and who decides them?"
Professor Paul de Waart, the professor emeritus of international law at the Free University in Amsterdam agreed that the reputation of the World Court in The Hague was on the line. But he had an important qualification.
"There is no doubt that if they go into the issues, they will have to say that it is illegal to build the wall into Palestinian territory and cut off Palestinian villages. If their decision goes the other way, the position of the court will be damaged in the eyes of large parts of the world."
Head of research at TMC Asser Institute
"If the judges' arguments are good enough to believe in, there will be no problem," he said. "But if they are not convincing, then the court may face the same situation as it did in 1962 when it refused to deal with the contentious case involving Namibia."
"That paralysed the court for another 14 years."
The case between Ethiopia and Liberia on the one side and South Africa on the other, proved to be the catalyst for an international campaign to boycott the apartheid state. The trigger was a ruling in favour of South Africa.
While Israel claims that a court decision on what Palestinians call the "Apartheid Wall" today is of no legal consequence, the parallels are obvious to many.
Many took to the streets to
condemn the building of the wall
Dr Ribbelink said that a ruling against the wall would have an enormous impact".
"It would have a negative effect on Israel's position,” he said. "It would further its isolation and strengthen calls for boycotts.
"The Court is the highest organ of the UN, if not the world, and the impact of its interpretation of the law is of enormous importance.”
Peter Bekker agreed: "It will be hard for Israel to go against the authority of the international court. This ruling might not be binding but it is the same process that the court goes through in order to come to a binding judgment in a contentious case between two states."
He added that the court's decision to invite a Palestinian delegation to participate had already made history. "It has never happened before that a non-state entity has been invited - and has participated - in proceedings," he said.
"It is unprecedented and shows that the court is aware of the importance of including Palestine in considering this legal matter."
In court today, attention was focused on a submission by the leader of the Jordanian delegation, Prince Zeid bin Raad. He described the bomb attacks in Israel as "nothing short of horrific" but cautioned against analysing them in isolation.
"It has never happened before that a non-state entity has been invited - and has participated - in proceedings."
Peter Bekker, senior counsel for the official Palestinian delegation
He said: "They must be weighed against four decades of Israel dominating and degrading an entire civilian population, often unleashing practices that have been no less horrific, resulting in civilian casualties."
"If Israel has a security problem, it can take measures within its own territory. This wall is not a fence, it dominates the surroundings, separates people from their land, divides communities and cuts a swathe through towns and villages."