Joe Oliver, the man who has publicly defended Trayvon Martin shooter George Zimmerman, endured a contentious interview on MSNBC's The Last Word Tuesday evening, admitting that his role in the story "doesn't make sense."

Host Lawrence O'Donnell and New York Times columnist Charles Blow criticized Oliver by questioning how close he actually is to Zimmerman. The back and forth exchange lasted almost a half an hour with O'Donnell being puzzled over Oliver believing Zimmerman's account of the shooting based on a 'gut feeling.'

"Joe, you're a mystery man to me," O'Donnell said. "Because you're doing this on such a slim basis of a gut feeling. You're given up your job. I don't understand how you've given up your job and your income to go out here and go out here and do this public relations job for George Zimmerman. I don't understand how you can afford to do this. It's strange, to me, behavior Joe. It doesn't add up to me. You're roll in this Joe, just doesn't make sense."

Oliver, who said he was more of an "older uncle" than a "close friend" of Zimmerman, agreed with O'Donnell's assessment. However, he continued to defend Zimmerman, calling him a "very good person who grew from his previous mistakes."

O'Donnell lashed at Oliver, saying he didn't have a consistent story on Zimmerman and that "there's so much he doesn't know" about him.

Blow added: "You don't know anything about George Zimmerman! You don't know if he's on the phone all the time, thinking that people are suspicious, whether they are seven or nine-years-old playing in a drive way or calling on Trayvon Martin. You don't know George Zimmerman. You know a little bit about this guy."

WATCH: Video from MSNBC, which was broadcast on March 27, 2012.

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