HERE we go again. The Special Tribunal for Lebanon, a United Nations-backed body investigating the killing of Lebanese Prime Minister Rafiq Hariri in 2005, has accused four people of his murder. They all belong to Hezbollah, the militant Lebanese Shia movement that Israel and the United States define as terrorist. But they are probably not guilty.

Special tribunals of this kind have no intelligence agents of their own. They rely heavily on information provided by national intelligence services that they trust. They don't seem to understand that there is no such thing as a trustworthy intelligence service.

Immediately after the explosion that killed Rafiq Hariri and 22 other people in Beirut, western and Israeli intelligence services said that the Syrian and Iranian governments were behind it. The main aim of the US and Israel at that time was to get Syrian troops out of Lebanon, who were stationed there since shortly after the start of the Lebanese civil war in 1975.

Four Lebanese generals accused of working for Syria were arrested. The non-violent “Cedar Revolution” broke out, demanding an end to Syrian meddling in Lebanese politics. And in the end the Syrians left and a pro-western government took power: mission accomplished.

But there was actually no evidence against the four Lebanese generals, and the Special Tribunal for Lebanon, soon after its creation in 2009, ordered their release. So who had organised the killing of Hariri, then? Well, accusing the Syrians had worked pretty well for the western intelligence agencies. Maybe they decided to blame Hezbollah now, and see if that worked too.

Hezbollah came into existence in response to the long Israeli occupation of southern Syria (1982-2000). It has the support of most of Lebanon's Shias, who dominate the south. And it gets arms and money not only from Syria but also from Syria's ally, Iran.

During the last Israeli attack on Lebanon, in 2006, Hezbollah fought the Israeli army to a stand-still in southern Lebanon. But its leadership has always been intelligent and subtle, and the notion that it would let itself become a tool for some ham-fisted Syrian operation to kill the Lebanese prime minister seems simply unbelievable to most Lebanese.

The judges of the Special Tribunal for Lebanon were persuaded by evidence that western intelligence services pointed them towards, particularly about mobile phone calls allegedly made by Hezbollah officials. So arrest warrants have now been issued for Mustafa Badreddin, Hezbollah's chief operations officer, and three other Hezbollah officials.

They probably had nothing to do with Hariri's assassination. It's more likely that they are being framed by western intelligence agencies because Hezbollah is seen a serious threat to Israel. If this sounds paranoid, consider the case of the Lockerbie bombing.

The bombing of Pan Am flight 103 in 1988 killed 270 people, most of them American. At first US intelligence blamed Iran, claiming that it used an Arab terrorist group based in Syria to carry out the operation. So Syria was under pressure too — but then in 1990 Saddam Hussein attacked Kuwait, and Washington needed the Syrians as allies in the war to liberate it. Suddenly the whole Iran-Syria case was abandoned, and the new suspect was Libya.

Libya under Muammar Qadhafi was an enemy of the west, so new evidence was found linking Libyan intelligence agents to the attack. Qadhafi was brought to heel, and one Libyan intelligence officer, Abdelbaset al-Megrahi, was tried by an international court and sentenced to life in prison. Alas, the new “evidence” was then gradually discredited as key “witnesses” turned out to be incredible.

One man, a Maltese shopkeeper called Tony Gauci whose testimony apparently linked al-Megrahi to the suitcase that contained the bomb, was later found living in Australia on several million dollars that the United States had paid him for his testimony.