"A lot of the cases after 9/11 were manufactured or enormously exaggerated and were announced with great trumpets by the attorney general and the FBI director so that we felt that they were doing something when, in fact, what they were doing was not helpful, not relevant, not needed," said Clarke.
While Assaad's undercover work has been called invaluable by the government in making the U.S. safer and has resulted in successful stings of alleged terrorist cells across the country, defense attorneys call him a master of entrapment against what they consider harmless targets.
After a 2006 sting, then-Attorney General Alberto Gonzalez praised Assaad – who was still unnamed at the time – for disrupting a group preparing a violent attack, resulting in the indictments of seven men on terror charges.
FBI undercover video from the case, obtained by ABC News, shows Assaad leading seven young men from Miami's inner city in a loyalty oath to Osama bin Laden, in which he persuaded them he had been sent by al Qaeda with tens of thousands of dollars to spend on them for weapons and training. The tape shows Assaad , who was working with the South Florida Joint Terrorism Task Force at the time, hugging his targets and welcoming them to al Qaeda.
Another video of a later meeting shows Assaad counting out $1000 for the leader of the Miami group.
After three trials, including two mistrials, five of the seven men were convicted.
Alleged Law Enforcement Entrapment
Defense lawyers including attorney Richard Houlihan, who represented Naudimar Herrera – one of the two men who were found not guilty, called the case a classic example of law enforcement entrapment.
"Without [Assaad's] performance, none of this would have happened," Houlihan told ABC News. "He's dealing with seven basically inner-city kids from Liberty City. Poor, uneducated, looking for money."
Herrera said he and the others played along with Assaad because of the financial incentives promised by him.
"He was like, "Oh your name here. You say your name here." It was more like, it was more like a movie script," Herrera told ABC News. He said that anyone "blind about greed" would be "vulnerable to [Assaad's] intelligence."
Assaad said some tactics – like suggesting targets, as he did in this case with FBI offices in Miami – are necessary in undercover stings.
"Sometimes you have to see…what he's willing to do….what's he's capable of doing," says Assaad of suspected terrorists.
"When you are working undercover," Assaad says, "your job is to lie."