Giuliani left the Iraq Study Group last May after just two months, walking away from a chance to make up for his lack of foreign policy credentials on the top issue in the 2008 race, the Iraq war.

He cited "previous time commitments" in a letter explaining his decision to quit, and a look at his schedule suggests why - the sessions at times conflicted with Giuliani's lucrative speaking tour that garnered him $11.4 million in 14 months.

Giuliani failed to show up for a pair of two-day sessions that occurred during his tenure, the sources said - and both times, they conflicted with paid public appearances shown on his recent financial disclosure. Giuliani quit the group during his busiest stretch in 2006, when he gave 20 speeches in a single month that brought in $1.7 million.

On one day the panel gathered in Washington - May 18, 2006 - Giuliani delivered a $100,000 speech on leadership at an Atlanta business awards breakfast. Later that day, he attended a $100-a-ticket Atlanta political fundraiser for conservative ally Ralph Reed, whom Giuliani hoped would provide a major boost to his presidential campaign.

The month before, Giuliani skipped the session to give the April 12 keynote speech at an economic conference in South Korea for $200,000, his financial disclosure shows.

Giuliani's campaign said that the former New York mayor did participate in Iraq Study Group activities but refused Newsday's repeated requests to explain how.

Instead, they referred to a May 24, 2006, letter Giuliani sent to the Republican co-chairman and former secretary of state James Baker. In it, Giuliani praised the group's "truly important mission" but cited his time commitments for why he couldn't give the group "the full and active participation" it deserved.

One source familiar with the group's activities recalled that Giuliani did participate in an early conference call in spring 2006 that was mainly organizational. But Giuliani's name is mentioned nowhere in the group's final report, which lists more than 160 people who were consulted.

By giving up his seat on the panel, Giuliani has opened himself up to charges that he chose private-sector paydays and politics over unpaid service on a critical issue facing the nation.

Not only that, but the 10-member group - also called the Baker-Hamilton commission - was no ordinary blue-ribbon panel, instead chartered by Congress and encouraged by the president to find a way forward in Iraq.

Giuliani's move already has come under attack by Democrats, and outside experts say it shines a light on his priorities at the time.

"Missing one meeting, you could put it down to staff error, but when you're missing them consistently, your priorities have been indicated, and the staff knows when there's a choice, you go on the road and pick up some bucks," said Kent Cooper, co-founder of Political Money Line, which tracks money in politics.

The Iraq Study Group held nine official meetings, which it called "plenary sessions," according to its final report. They included three that occurred during Giuliani's tenure in 2006 but that he did not show up for, the sources said - working sessions on April 11 and 12, and May 18 and 19. There was also a kickoff event on March 15 that Giuliani and several other members did not attend, the sources said.

By quitting the panel, Giuliani also passed up a chance to fill another big gap in his commander-in-chief credentials - Giuliani said recently he's never been to Iraq, unlike his top declared GOP rivals and several in the Democratic field. Baker and Democratic co-chairman, former Rep. Lee Hamilton, led a four-day Iraq trip last summer.

Giuliani has faced questions of why he hasn't been to Iraq despite being an enthusiastic supporter of the Iraq war. He has said a planned trip was scuttled for reasons he didn't specify but that he hopes to go by year's end.

Pentagon officials said they are not aware of a request by Giuliani to travel to Iraq and that it could be somewhat difficult to achieve at this late date.

When Giuliani failed to attend the first two working sessions, his absences didn't sit well with Baker - particularly when the other luminaries who made up the panel were able to make the sessions in Washington, some sources said. Baker's policy assistant John Williams said the choice to quit was entirely Giuliani's.

"Baker felt that it was important for future meetings that people show up, so that left the decision on Giuliani whether he would make it or not," Williams said. He provided a copy of Giuliani's letter to Baker and declined further comment. Former U.S. attorney general Edwin Meese III replaced Giuliani on the 10-member panel a week later.

President George W. Bush was initially cool to the group's December recommendations, which included a goal of pulling out most U.S. combat troops by early 2008 and beginning unconditional talks with Iran and Syria, but lately he has moved to embrace some of them.

At least one Democratic member of the group questioned Giuliani's decision to quit. "It would have better served him politically to be a part of the group, because every candidate needs an answer to the question - what the hell would you do in Iraq?" said Leon Panetta, a former chief of staff to President Bill Clinton.

Three other Democratic members refused to comment, and former Wyoming Sen. Alan Simpson, a Republican member of the panel, didn't recall that Giuliani had been picked. Asked if he thought Giuliani would have benefited from staying on the panel, Simpson said, "You'd have to ask Rudy that."

Stephen Hess, who has served as an adviser to presidents from both parties, said quitting the group is likely to pose a political problem for Giuliani. "Leaving that study group was not exactly an act of courage," said Hess, particularly because the group's recommendations ultimately diverged from Bush's stick-it-out approach, which Giuliani has embraced.

When the group's report came out last December, Giuliani offered a different reason why he quit, saying he didn't think it was right for an active presidential candidate to take part in such an "apolitical" panel. Giuliani also took pains at the time to distance himself from some of the group's findings.

At some point, Baker spoke to Giuliani to find out if he intended to continue his involvement with the group. "He basically said, if people can't make the meetings, we've got to find people who can," Panetta recalled.

Asked if he knew what Giuliani was doing instead of attending the meetings, Panetta joked, "I'm sure making a hell of a lot of money."

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Timothy M. Phelps and Tom Brune of the Washington Bureau contributed to this story.

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