(CNN) Former New York City Mayor Rudy Giuliani spent his Sunday "defending" Donald Trump and "advocating" for the President's innocence as it relates to the ongoing investigation into Russian interference in the 2016 election.

He did an extremely poor job of it -- creating any number of problematic storylines for the President, including an acknowledgment that Trump's team had conversations with Russians about a business venture in Moscow far longer into the 2016 election than had been previously known.

But this exchange -- between Giuliani and ABC's George Stephanopoulos -- really took the cake for me. It begins with Giuliani bashing former Trump lawyer/fixer Michael Cohen, who is now a cooperating witness in the probe, as a liar:

GIULIANI: "And the Southern District says you can get out of jail if you do this, you've got three years now. There's a real motivation to sing like crazy. He's got to do a lot of singing to get out of the three years and he will say whatever he has to say. He's changed his story four or five times."

STEPHANOPOULOS: "So has the President."

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