An undated file photo of Michael Bloomberg.

An undated file photo of Michael Bloomberg. Credit: Getty Images

Mayor Michael Bloomberg testified Monday against a former campaign operative accused of bilking him out of more than $1 million, then underwent hours of cross-examination by a defense lawyer who questioned whether he had skirted the law and came close to calling the billionaire politician a liar.

"He promised things that he didn't do," Bloomberg said of John Haggerty, who is accused of persuading the mayor and his staff to finance an expansive poll-monitoring initiative that never materialized, then using most of the cash to buy himself a house.

"Isn't that what you regularly did at Salomon Bros.?" lawyer Raymond Castello responded.

Castello asked the mayor a number of potentially uncomfortable questions, reading from a passage in his autobiography in which he said that as a businessman he had promised customers more than he planned to deliver. He also brought up topics that could be unpopular with voters and jurors -- from Bloomberg's flip-flop on extending term limits to his decision to keep an aide's domestic-violence arrest private even when publicly announcing his departure.

"I don't lie," the mayor said.

Bloomberg, for his part, remained calm but wary on the stand, even when Castello raised his voice and repeatedly pointed his index finger at the mayor. Bloomberg at one point appeared bemused when he was confronted with the words from his autobiography, smiling as he considered the text.

The defense has sought to paint a picture of a high-rolling candidate surrounded by privileged insiders who dodged ethics rules, threw money at problems and didn't hesitate to bend the law. But prosecutors do not accuse the mayor of any wrongdoing, and Bloomberg's representatives have said his campaign broke no laws and followed standard practices.

Haggerty, 42, presented Bloomberg campaign aides with a budget for a 2009 "ballot security" operation, to be financed through a personal gift from Bloomberg to the state Independence Party. The Democrat-turned-Republican-turned-unaffiliated Bloomberg was then running for a third term on the Independence Party, Republican and other lines.

Bloomberg said he never would have donated the money to the party if he had thought it wouldn't be used on a poll-monitoring operation.

"I know exactly what we paid $1.1 million for, and my understanding is that we did not receive that service," he said.

The defense argues that prosecutors can't prove the money was stolen because the mayor's donation to the party was placed in a fund that could not legally be earmarked for a specific purpose.

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