Robert Gamburg confronted Nutter after the news conference, as Nutter chatted with reporters. He asked whether the mayor was aware that he was in the process of arranging to pay his taxes.

"I'd also like to know if we are the only three people in the entire city that owe back taxes," Gamburg said, and wanted to know why Nutter chose his building to hold the news conference.

"I'm not going to argue with you on the sidewalk - you owe the city money, pay your taxes," Nutter said.

When Gamburg questioned why Nutter was getting "upset," Nutter raised the bar.

"Oh, you've never seen me upset," Nutter said. "So I'm not upset. Just pay your taxes and everything will be fine."