The first public hearing has been held at the Hariri tribunal in the Dutch town of Leidschendam near The Hague. The tribunal is dealing with the assassination in 2005 of Rafik Hariri, former prime minister of Lebanon, in which 23 people were killed. Here are five questions and answers about the tribunal.

Why is the tribunal important?

It is the first ever fully international terrorism tribunal. The reason the case is not being brought before the International Criminal Court in The Hague is because this court only deals with cases involving genocide, war crimes and crimes against humanity, and not terrorism. The Hariri tribunal is jointly financed by the United Nations and the state of Lebanon.

Who is on trial?

The people or persons behind the assassination of Rafik Hariri will be tried. The perpetrators are almost certainly members of the extremist Lebanese Hezbollah movement. The formal charge is secret. As is the identity of those to be tried. A so-called 'pre-trial' judge will decide whether or not there is sufficient evidence to start the trial. Only then will the suspects be arrested and the charges made public. This information is being withheld because if it were made public it could hamper the investigation and arrest of the suspects. Proceedings in the Yugoslavia tribunal was made more difficult by this kind of information coming out before the trial.

Hezbollah has asked the new Lebanese government to withdraw its support for the tribunal. Is the trial still in with a chance of success?

Hezbollah regards the tribunal to be a political trial, set up by the United States and Israel to put the organisation in a bad light. Last month, the organisation withdrew from government, forcing new elections. As a result, Rafik Hariri’s son, Saad al-Hariri,  who was prime minister has been succeeded by Hezbollah-backed Najib Mikati. Hezbollah has asked the new prime minister to withdraw his support from the tribunal.

However, Geraldine Coughlan, Radio Netherlands Worldwide’s reporter for International Justice, does not think it is likely that this will happen.

“The Lebanese government will not actually withdraw its support from the tribunal, because the government is cooperating with the UN Security Council. The tribunal was set up on the basis of an agreement between the Security Council and the Lebanese government in 2006. It already exists and will certainly continue. However, there are fears that naming possible Hezbollah members could lead to increased tension and fighting could break out in Lebanon.”

What is the objective of the tribunal?

As a result of its turbulent political history, Lebanon has a long list of political assassinations, for which in almost every case no-one has been prosecuted. The Hariri tribunal has to break this pattern. The prosecution of the people behind the assassination is meant to act as a deterrent.

Why is the term terrorism only being defined now?

The international tribunal is a unique project. It will partly be based on Lebanese law and partly on international law. This is why all kinds of terms have to be redefined, says Geraldine Coughlan.

“Terms like conspiracy, terrorism and assassination have not been adequately defined in international law. So the terms have to be clearly defined first in consultation with the judges, the defence, and the prosecution. Only once this has been done, can the charges be formulated and made public.”