Cast into the unfamiliar role of courtroom witness, the man now known as America's mayor refused to concede he may have spoken out against the men too aggressively and denied he forced them out for political gain.
In a testimony that stretched unbroken for three hours and 20 minutes, Giuliani recounted how he had been deeply offended when he learned a police officer and two firefighters had taken part in a Labor Day parade float in 1998 that made a joke out of a horrific racist crime.
"My response was that it was very offensive, it was outrageous and that it had the potential of causing severe disruption, civil unrest - it concerned me greatly," he said.
He said the men - ex-cop Joseph Locurto and ex-firefighters Jonathan Walters and Robert Steiner - acted highly unprofessionally, endangered their colleagues and disrespected their uniforms.
The men are suing the city, claiming their firings breached their rights to free speech.
Giuliani, wearing his customary red tie and American-flag lapel pin, agreed he had publicly said, within days of the incident, that the only way Locurto would get his job back was if the Supreme Court "tells us to put him back."
With fears rising that the incident could trigger racial violence, the mayor said it was important that he assure New Yorkers the trio would be fired - even though that decision rested entirely with then-Police Commissioner Howard Safir and then-Fire Commissioner Thomas Von Essen.
In a series of frank remarks, Judge John Sprizzo told the mayor his comments might have been inappropriate, saying, "If you had just gone weaker, you may not have had the political impact, but you wouldn't be here today."
But Giuliani argued his comments were really a "prediction" and Safir and Von Essen were "independent commissioners" capable of making their own decision.
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