A few months after he left his gig as a Fox News television host to pursue the Republican nomination for president in 2016, former Arkansas Gov. Mike Huckabee was back on Fox News Sunday, and to put it mildly, things did not go well.

While Fox has a reputation for being friendly, sometimes overly so, toward the GOP, Fox News Sunday host Chris Wallace is usually an equal opportunity interrogator, and he didn’t hesitate to ask his former colleague to explain some of his more controversial claims.

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Huckabee, for instance, is an advocate of the “FairTax” plan, which would eliminate the income tax and replace it with a consumption tax of about 30 percent while remaining revenue-neutral. Tax experts have repeatedly exposed the FairTax plan as highly regressive – meaning that lower-income individuals would pay a higher percentage of their income in taxes than the wealthy.

It was a point Wallace asked Huckabee to address, quoting an analysis by the Urban-Brookings Tax Policy Center which found that “the average rate of the lowest income group would exceed 33 percent, while the average for the top group would fall to less than 16 percent.”

“They have it exactly wrong,” Huckabee said. “In fact, it’s the bottom third of the economy who benefit the most from the FairTax, and the people at the top third who benefit the least Everybody benefits some. That tax study is one that has been discredited by the people who spent over $20 million, very thoughtful economic study developing the FairTax. It’s not just some political idea….“

Wallace interrupted, “Doesn’t it just stand to reason that if I make $5,000, I’m going to spend a higher percentage of my income just for necessities, and if I make $1 million, I’m not going to spend as much of a percentage of my income?”

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Huckabee launched into an explanation of what FairTax advocates call a “prebate.” Under the proposal, the government would send a check every month to every taxpayer equivalent to what someone living at the poverty level would pay in taxes for “necessities.” He claimed that the prebates mean low-income earners do better under the system than they do currently.

“The FairTax empowers the consumer,” Huckabee said. “That’s power to the people.”

As it turns out, though, the folks at the Tax Policy Center don’t take kindly to having their analyses described as “discredited” on national television.

Asked to respond to Huckabee, William Gale, co-director of the Center, delivered a withering email takedown of Huckabee’s claims and the FairTax proposal in general.

“He has the distributional benefits backwards,” wrote Gale, a senior fellow at the Brookings Institution and a former senior economist for President George H.W. Bush’s Council of Economic Advisers. “The notion that a tax on consumption will help the poor and hurt the rich is contrary to just about everything that is known about rich/poor spending and income habits, not just our model.”

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In a swipe at the FairTax program, he added: “The ‘people who spent over $20 million on this' did not understand for a decade how the tax actually worked, and it took two papers by me as well as other work – for example, the Bush tax reform panel – to convince these people that they had vastly misstated the tax base because they made 20-25 percent of government disappear.”

Len Burman, the director of the Tax Policy Center, joined the fray as well. Also by email, he said that the idea that the poor would do better under the FairTax plan is simply wrong.

“This issue doesn't involve complicated economic analysis,” wrote Burman, who among other things served as a deputy assistant secretary for tax analysis in the Clinton Treasury Department. “It's simple math, and the FairTax advocates have repeatedly and willfully flubbed the math.”

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“The distributional effects are pretty straightforward,” he wrote. “High-income people spend only a fraction of their income, so they effectively benefit from a giant tax exemption compared with an income tax.”

In the Fox interview, Wallace eventually let Huckabee wriggle away from the tax issue, but moved on to some other interesting claims the former governor has recently made – including a suggestion that presidents and lawmakers don’t necessarily need to abide by the rulings of the Supreme Court.

Huckabee claimed that the United States has fallen victim to what he called “judicial supremacy,” in which the Supreme Court has set itself above the other branches of the government.

“The Supreme Court isn’t the Supreme branch, and for God’s sake, it isn’t the Supreme Being,” he said. Wallace, who had not suggested that the Supreme Court was in any way God-like, had no answer for that one, and Huckabee was off, dropping straw man arguments as he went.

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“It’s a matter of balance of power,” he said. “If the Supreme Court could just make a ruling and everybody has to bow down and fall on their faces and worship that law – it isn’t a law because it hasn’t been yet passed.”

Umm…

“What if the Supreme Court ruled that they were going to make the decision as to who is going to be the next president and save the taxpayers and the voters from all the expense and trouble of voting and they’ll just pick a president? Well we would say that they can’t do that. Why can’t they do it? They can’t do it because it’s not in the law,” Huckabee continued.

But wait, nobody said….

“We are sworn to uphold the Constitution and the law and it has to be agreed on by three branches of government. One can’t overrule the other two,” He said “That’s all I’m saying. We learned that in 9th grade civics, but I’m convinced a lot of Ivy League law schools must have forgotten that simple, basic civics lesson along the way.”

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Okay, enough.

That’s just not true. A bill passed by Congress and signed into law by the president can be declared unconstitutional by the Supreme Court. That’s pretty much the definition of one branch overruling the other two.

Sometimes it’s a little difficult to tell if Huckabee is actually mounting a presidential campaign or just an extended book tour for his latest tome, God, Guns, Grits, and Gravy. On Sunday, it felt a lot like the latter.

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