By Mark Hosenball and Michael Isikoff

The ruling by an Italian judge convicting 23 Americans—including several CIA officers—of plotting the abduction of a Muslim cleric is a milestone verdict on several fronts. It represents the first legal judgment by a foreign court that elements of the Bush administration's post-9/11 counterterrorism policies involved the commission of criminal acts. Even if none of the convicted CIA officers are ever extradited to Italy and forced to spend any time in jail—as they probably won't be—they could face standing arrest warrants that will almost certainly prevent them from traveling anywhere in Europe for the foreseeable future.

The ruling also places a renewed spotlight on one controversial Bush policy that the Obama administration has not yet totally disavowed: the practice of extralegal "extraordinary renditions" by which terror suspects are seized and sent to foreign governments without any legal process.

"This is an important verdict—it's a legal ruling that the CIA's rendition program involved crimes," says Joanne Mariner, the counterterrorism director of Human Rights Watch who was in the courtroom in Milan when the judge, Oscar Magi, handed down his ruling. While acknowledging that none of the CIA officers are likely to face any time in prison, "you can be certain that none of the defendants will be traveling to Europe," said Mariner.

Wednesday's ruling centers around the CIA organized kidnapping off the streets of Milan of Egyptian-born Osama Mustafa Hassan Nasr, also known as Abu Omar. An Islamic cleric suspected of preaching violence, Abu Omar was flown to Egypt where, he later alleged, he was subjected to brutal torture that included being hung upside down and having live electronic prods applied to his genitals. He ended up spending four years in a Cairo prison, but was later released. The Italian judge today awarded him and his wife €1.5 million (about $2 million) in damages for his suffering. (A CIA spokesman said today the agency would have no comment on anything related to the Abu Omar case.)

Among those convicted in the case of participating in his abduction was Robert Seldon Lady, alleged to be the CIA's former chief officer in Milan, who received an eight-year prison sentence while being tried in absentia. Three of the defendants, including Jeff Castelli, the CIA's former Rome station chief, were granted diplomatic immunity. Among others convicted was Sabrina De Sousa, ostensibly a State Department official who worked closely with Lady. One of the arguments used by De Sousa's lawyer was that she was following the orders of superiors. "Everything I did was approved back in Washington," DeSousa told ABC News correspondent Brian Ross in an interview scheduled for broadcast Wednesday night. But Armando Spataro, the veteran counterterrorism prosecutor in charge of the case, gave an impassioned two-hour speech in the courtroom in which he dismissed that argument as the "Nuremberg defense," according to Mariner.

The convictions were handed down despite an aggressive behind-the-scenes effort by the U.S. government to persuade Italian authorities to close and bury the case, which represented a major embarrassment for the CIA. This was among the first official investigations to expose details of the agency's "extraordinary rendition" program; although the "rendering" of some terror suspects had taken place in past administrations, those almost always involved bringing the targets to countries where they faced legal charges. After 9/11, the Bush White House authorized the CIA to dramatically escalate renditions, resulting in the snatching of dozens of suspects around the world, where they were flown to countries such as Syria, Jordan, and Egypt—not to stand trial but to be interrogated. The countries where the suspects were flown had also long been criticized by the State Department for engaging in torture. One of the first suspects, Ibn al-Shaykh al-Libi—who was rendered to Egypt and later made false claims tying Saddam Hussein to Al Qaeda after allegedly being tortured—was reported to have been found dead in his prison cell in Libya earlier this year.

The Italian prosecution was also embarrassing for the CIA for other reasons: the evidence gathered by Italian investigators showed remarkable sloppiness in the "tradecraft" the CIA perpetrators employed when they carried out the operation. Evidence produced by Italian investigators portrayed the CIA operation as almost laughably inept, like something out of a bad spy comedy. According to court documents, Italian authorities tracked down members of the purported CIA rendition team through cell-phone calls they made near the location where Abu Omar was seized. Investigators also reportedly collected credit-card payments showing that members of the CIA team rang up substantial car-rental and luxury-hotel bills.

Since taking office, the Obama administration has strongly distanced itself from many of the most controversial elements of CIA counterterrorism operations launched by the Bush administration. The Obama White House announced it had shut down a network of secret CIA terrorist-detention facilities and that the CIA will no longer carry out the kind of "enhanced" interrogations approved by the Bush Justice Department. But Obama officials were careful not to announce any ban on future agency operations involving rendition. Instead, they say, they have taken steps to curb abuses—such as directing agencies to ensure that transfers are lawful and that countries to which suspects are sent do not practice torture. Even before it left office, the Bush administration had started seeking stronger "assurances" from foreign governments that they wouldn't torture suspects who were rendered to them.  Former Bush administration officials maintain they already instructed CIA officers in the field to carefully monitor the status and well-being of prisoners the agency had rendered. Nonetheless, human-rights groups remain skeptical of the entire concept of diplomatic assurances. "Diplomatic assurances are a farce," says Mariner. "They are a fig leaf."