"I would testify, I would do demonstrations, I'd give lectures, I'd give summations, or I'd do what I do best, I'd try the case. I'd love to try the case," Giuliani told reporters as he made his way into a New Year's Eve celebration at the president's Florida resort on Tuesday night.
Giuliani, a former federal prosecutor, suggested he'd lead the president's defense with a prosecution.
"I don't know if anybody would have the courage to give me the case, but if you give me the case, I will prosecute it as a racketeering case, which I kind of invented anyway," he said, referring to his pioneering use of racketeering laws to take down New York mob leadership in the 1980s.
"It was 30 years ago, but let's see if I can still do it," he said.
The former New York City mayor did not elaborate, but he has said before that Trump did nothing wrong in the dealings with Ukraine that led to his impeachment, and that the real wrongdoers are former Vice President Joe Biden and his son.
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The impeachment proceedings center on Trump's efforts to press Ukraine's president to investigate the Bidens, focusing on Hunter Biden's work on the board of a Ukrainian gas company while his father was calling for the removal the country's top prosecutor as part of the Obama administration's anti-corruption efforts there. Trump sought the investigation into his political rival while while withholding critical military aid to the country, which is at war with Russian-backed separatists.
The Bidens have denied any wrongdoing.
Trump's allies and top Republicans have urged the president to distance himself from Giuliani, who is reportedly being investigated by federal prosecutors who have arrested two of his associates on charges of violating campaign finance laws.
Giuliani has denied any wrongdoing, telling New York magazine in an interview published last week that if prosecutors are investigating him, "they're idiots."
In that same interview, Giuliani said he wanted to represent Trump in the Senate so he could cross-examine Democrats.
"I'm great at it. It's what I do best as a lawyer. That's what I would be good at," he said. "Oh, I would love it, I could rip — you know, I hate to sound like a ridiculously boastful lawyer, but cross-examining them would be, I don't know, I could've done it when I was a second-year assistant U.S. attorney. They're a bunch of clowns."
Giuliani's claims that the Bidens were involved in criminality in Kyiv — for which there's no credible evidence — led to Trump's demand that the country investigate the father and son, which resulted in the president's impeachment.
Trump was not asked about who would represent him in the Senate trial as he made his way into the party at Mar-a-Lago, but he did sound off on his impeachment, which he called "a big fat hoax."
"As far as I'm concerned I will be happy with the trial because we did nothing wrong," he said.