The hearing by the Special Tribunal for Lebanon is the first since Maj. Gen. Jamil Al-Sayyed, the former chief of general security, and three other pro-Syrian army officers were freed from a Lebanese jail for lack of evidence in April 2009.
The hearing, the first to be attended by reporters, will revive attention to a case that has been languishing. No other suspects are in custody and prosecutors decline to say how their investigation is progressing.
The four officers were detained two months after Hariri and 22 others died in a massive truck bomb explosion in Beirut, and suspicion fell on Syria and its Lebanese allies. Hariri, a billionaire businessman credited with rebuilding Lebanon after its 15-year civil war, had been trying to limit Syria's domination of Lebanon in the months before his assassination.
Since the release, investigators have interviewed members of Hezbollah militia, possibly exploring any link to broader Middle East rivalries.
Both Syria and Hezbollah have denied involvement.
Al-Sayyed said in his application to the court that his "arbitrary detention was based on libelous denunciations and false statements," and he intends to sue whoever was responsible.
He said "legal remedy" for his detention can only be found in his case file.
He also argued that court should prosecute "false witnesses who are vitally important to its mission," and said the number of witnesses against him "points to a premeditated plot." Uncovering who they are would help lead to those truly responsible, his application said.
Prosecutors have objected, saying the tribunal has no jurisdiction to release the file since Al-Sayyed is no longer a suspect and has no standing in the case. The tribunal's sole mandate is "to bring terrorists to justice," they said it a written response.
"The investigation is still ongoing. The prosecutor has not filed an indictment. Without an indictment there is no accused," the prosecution said.
Al-Sayyed was considered Syria's strongman in Lebanon. He and the other three generals directed the chief security, military intelligence services and the presidential guard.
They were instrumental in implementing Syrian policy in Lebanon.
Hariri was Lebanon's most prominent politician since the civil war ended in 1990. His death set off political turmoil in Lebanon that led to the withdrawal of Syrian troops after almost 30 years of military presence in the country.
The tribunal, set up by the UN Security Council in 2007, comprises seven foreign and four Lebanese judges, and is grounded in Lebanese law. The court is based in this suburb of The Hague to ensure the safety of the staff and an impartial trial.
