McCain claimed that it wasn't as easy for ordinary Americans, as it was for Behar, to ignore the question since the government would likely fine them thousands of dollars.
"You will be fined $5,000 to $10,000 if you don't answer it," McCain said, before adding, "I don't think the average American can afford 10 grand."
Behar responded by suggesting Americans could pretend they didn't see the question and that it would be difficult for authorities to punish everyone who refused to answer. "They can't put all of us in jail. We're about 200 some-odd million people in this country," she said in the Tuesday morning exchange.
After the camera panned to an apparently disturbed McCain, Behar said, "lock us all up." Behar argued that Trump wanted to add the census question so that he could eliminate competition for Republicans running for office.
Their comments came as the administration prepared to respond to a Supreme Court ruling pushing back on the Commerce Department's justification for adding the question.
On Monday, Deputy White House Press Secretary Hogan Gidley argued that the American people had a right to know who was in the country.
"It’s kind of fascinating to me, we're at a weird place in America when President Trump is being asked why he wants this question included in the census, and Democrats aren’t being asked why they don’t," Gidley told Fox News. "Everyone should want to know who’s in this country, and this is nothing new."
The question, Behar also said, would produce more favorable districting for Republicans. "They would like to make the country a Republican country without any competition — that's basically what they're doing," she said before describing their actions as part of a "coup." She later argued that Trump "should be embarrassed" that he can't win elections "legitimately."