By MICHAEL COOPER (NY Times November 30, 2007) In almost every appearance as he campaigns for the Republican presidential nomination, Rudolph W. Giuliani cites a fusillade of statistics and facts to make his arguments about his successes in running New York City and the merits of his views. Discussing his crime-fighting success as mayor, Mr. Giuliani told a television interviewer that New York was “the only city in America that has reduced crime every single year since 1994.” In New Hampshire this week, he told a public forum that when he became mayor in 1994, New York “had been averaging like 1,800, 1,900 murders for almost 30 years.” When a recent Republican debate turned to the question of fiscal responsibility, he boasted that “under me, spending went down by 7 percent.” All of these statements are incomplete, exaggerated or just plain wrong. And while, to be sure, all candidates use misleading statistics from time to time, Mr. Giuliani has made statistics a central part of his candidacy as he campaigns on his record. For instance, another major American city claims to have reduced crime every year since 1994: Chicago. New York averaged 1,514 murders a year during the three decades before Mr. Giuliani took office; it did not record more than 1,800 homicides until 1980. And Mr. Giuliani’s own memoir states that spending grew an average of 3.7 percent for most of his tenure; an aide said Mr. Giuliani had meant to say that he had proposed a 7 percent reduction in per capita spending during his time as mayor. Facts and figures are often the striking centerpieces of Mr. Giuliani’s arguments. He has always had a penchant for statistics — his anticrime strategy as mayor was built around a system known as Compstat that closely tracked crimes to focus law enforcement efforts. On the campaign trail he often wields data, without notes, with prosecutorial zeal to hammer home his points. But in recent days, both Mr. Giuliani’s Republican rival Mitt Romney and Democrats have accused him of a pattern of misleading figures and have begun to use the issue to try to undercut his credibility. An examination of many of his statements by The New York Times, other news organizations and independent groups have turned up a variety of misstatements, virtually all of which cast Mr. Giuliani or his arguments in a better light. “He’s given us a lot of work up until now,” said Brooks Jackson, the director of Annenberg Political Fact Check, which is part of Factcheck.org, a project of the Annenberg Public Policy Center of the University of Pennsylvania that has corrected statements by candidates in both parties. Aides to Mr. Giuliani dismiss questions about his use of statistics as nitpicking, arguing that no one can dispute the big points he makes by using the statistics: that crime dropped significantly during his tenure, say, or that he worked to restrain spending in New York. “The mayor likes detail, and uses it frequently on the campaign trail in ways the other candidates don’t,” said Maria Comella, a spokeswoman for Mr. Giuliani. “And at the end of the day, he is making points that are true.” Mr. Giuliani is not alone in citing statistics in a questionable way. Last month, Senator Hillary Rodham Clinton, Democrat of New York, said that financing for the National Institutes of Health had decreased under President Bush; it has increased. Senator Barack Obama, Democrat of Illinois, said the national debt had doubled under President Bush; it has not. But with Mr. Giuliani running so strongly on his record, statistics have taken on a central role in his campaign. In recent days, Mr. Giuliani seems to be taking greater care to be precise. At the Republican debate on Wednesday night, he was careful when referring to crime statistics in Massachusetts during Mr. Romney’s term as governor, which had been the subject of a debate over the weekend. And at a “Politics and Eggs” breakfast on Monday in Bedford, N.H., he took greater care to describe his record on cutting taxes. Last weekend, speaking about his belief in supply-side economics, Mr. Giuliani said, “I lowered, argued for lowering, and got the hotel occupancy tax lowered by 33 percent. And I was collecting $200 million more from the lower tax than the city had been collecting from before I was mayor from the higher tax.” In fact, the increase in revenues from the hotel occupancy tax was just over a quarter of what Mr. Giuliani asserted — the city’s hotel tax revenues grew by roughly $58 million during his term, according to the city’s Independent Budget Office — and a booming economy, as well as the reduction in crime Mr. Giuliani helped produce, probably played a part. Factcheck.org has reported that the Giuliani campaign exaggerated when it boasted on its Web site that “Mayor Giuliani increased the police force from 28,000 to 40,000,” noting that most of that increase came from his merger of the Transit and Housing Police Departments with the New York Police Department, a transfer of more than 7,000 existing officers to the department. The campaign argues that giving housing and transit police officers jurisdiction beyond the city’s public housing and subways gave the city more flexibility to fight crime. It said that it usually notes the effects of the merger when describing the size of the police force, and said it would change a post on its Web site to mention the merger when citing the increase. And the group also found that Mr. Giuliani erred at a Republican debate when, while calling for tort reform, he said that 2.2 percent of the nation’s gross domestic product “is spent on all these frivolous lawsuits.” That statistic, the group reported, came from a study that pegged the cost of all civil claims at 2.2 percent of the G.D.P., without judging whether the cases had merit or not. Even some people who support Mr. Giuliani’s proposals say he risks undercutting his own arguments when he relies on imprecise or questionable statistics. In a recent radio advertisement by the campaign about his health care proposal, Mr. Giuliani repeated another false statement that he had been using on the campaign trail. In the advertisement Mr. Giuliani, who has had prostate cancer, asserted that his chances of surviving prostate cancer in the United States were 82 percent, while his chance of surviving in England would have been only 44 percent. His point was that the American health care system is far superior to England’s government-run system, which he refers to as “socialized medicine.” The figure came from an article written by one of Mr. Giuliani’s health care advisers, but was soon discredited: the source of the research that was used to derive the statistic said that its data had been misused. The Office for National Statistics in Britain said that the true five-year survival rate was 74.4 percent — still lower than in the United States, but by a much smaller margin. Mr. Giuliani stood by the statistic, however, and kept using the advertisement, though it has since gone off the air. Ramesh Ponnuru, a senior editor at National Review magazine, said Mr. Giuliani’s plan “may be the best of the Republican health care plans.” “The trouble is that the exact statistic he used was misleading,” Mr. Ponnuru said in a recent interview, elaborating on a blog post he wrote. “It became an argument about the statistics, and he dug in and defended it when he was wrong.” Another radio advertisement that Mr. Giuliani ran over the summer stated that as mayor he “turned a $2.3 billion deficit into a multibillion-dollar surplus.” That was also misleading. According to independent fiscal monitors, Mr. Giuliani did have to close a $2.3 billion deficit in his first budget, and did accumulate a multibillion-dollar surplus during his tenure. But by Mr. Giuliani’s last full fiscal year in office, the city was spending more than it was taking in in revenues, and Mr. Giuliani ended up spending almost all of the surplus to balance his final budget. Last weekend, questions about Mr. Giuliani’s use of facts moved front and center in the campaign. Mr. Giuliani charged that “violent crime and murder went up” in Massachusetts while Mr. Romney was governor. The number of reported killings did go up in those years, but the state’s overall rate of violent crime went down, according to statistics compiled by the Federal Bureau of Investigation. Mr. Romney accused Mr. Giuliani of having “a real problem with facts,” and aides circulated a statement calling Mr. Giuliani’s crime statistics “about as accurate as his prostate cancer survival numbers for England.” “He has now done this time and again, making up facts that just happen to be wrong, and facts are stubborn things,” Mr. Romney said. Frank Luntz, a Republican strategist who once worked for Mr. Giuliani, said he doubted that the issue would hurt him politically. “When he talks about New York, people see it,” Mr. Luntz said of Mr. Giuliani, “and they feel it, and if a number isn’t quite right, or is off by a small amount, nobody will care, because it rings true to them.”