There undoubtedly are some Libyans who fear they may be implicated. There are also foreign intelligence services and political leaders who had shady dealings with Gadhafi's brutal dictatorship despite their governments' hostility to Tripoli over four decades.
These were the same governments that led the charge to topple the mercurial Gadhafi by providing air strikes to aid his enemies, and often targeted him, his sons and their families.
Indeed, during the eight-month conflict that began in February 2011, amid the initial upheavals of the so-called Arab Spring and its pro-democracy uprisings, many observers were convinced NATO was trying hard to kill Gadhafi to prevent him from being handed over to the International Criminal Court in The Hague to keep the murky dealings of their governments private.
"Imagine the stir he would have made in The Hague," observed author and commentator David Rieff in Foreign Policy in October 2011 after Gadhafi, on the run with his sons, was finally butchered on the streets of his hometown, Sirte, by a howling mob.
"There, along with any number of fantasies and false accusations, he would almost certainly have revealed the extent of his intimate relations with French President Nicolas Sarkozy and British Prime Minister Tony Blair, the details of his government's collaboration with Western intelligence services in counterterrorism, with the European Union in limiting migration from Libyan shores, and the granting of major contracts to big Western oil and construction companies."
There are fears the trials, which include 26 other regime figures, will be little more than legalized revenge against Gadhafi's family and his henchmen.
"There may be those who served Gadhafi who have no desire to see their crimes pushed out into the open," Lebanese political analyst Michael Young said.
"There are perhaps also many Libyans who fear that if the dark side of the dictatorship is revealed, it may hinder reconciliation."
Senussi, 62, the Libyan leader's brother-in-law, was his most brutal enforcer. He was known as "Gadhafi's black box" -- he knew where all the bodies were buried.
Senussi, Libyans said, was always among the Libyan leader's "ahl al-khaimah," the people of the tent, his inner circle. For two decades Senussi headed Libya's feared External Security Organization.
He was convicted in absentia by a French court in 1999 of masterminding the 1989 bombing of a UTA airliner over Niger that killed 170 people.
Western intelligence services have long suspected he played a key role in the December 1988 mid-air bombing of a New York-bound Pan Am jumbo jet over Lockerbie, Scotland, in which 270 people, mostly Americans, were killed.
Until Sept. 11, 2001, Lockerbie was the world's bloodiest terrorist attack.
Senussi is believed to have recruited intelligence agent Abdelbaset al-Megrahi, the only suspect convicted of bombing Pan Am 103.
It's an atrocity that remains largely unexplained. There are claims Iran was the real culprit and Gadhafi was scapegoated by the United States and Britain.
Libyan authorities have accused Senussi of other crimes, including the massacre of more than 1,200 Islamist detainees as Tripoli's notorious Abu Salim prison in 1996.
Senussi escaped Libya after rebels seized Tripoli in August 2011 and fled to Nouakchott, capital of Mauritania. He was arrested there in March 2012 for entering the country from Niger using a false passport.
He was extradited to Libya Sept. 5, 2012, despite being indicted in June 2011 by the ICC for crimes against humanity in Libya. He faces the death penalty if convicted in Tripoli.
Saif al-Islam, 39, was captured by a powerful tribal militia in southern Libya Nov. 19, 2011, and was held in the town of Zintan with his aides.
Gadhafi's second son and the most politically involved, he too was a member of his father's closest entourage and was seen as a possible successor.
Like Senussi, Saif al-Islam is also wanted by the ICC. He was at one time considered more liberal than his father, but he reportedly led regime forces involved in widespread atrocities during the uprising.