Republican Rep. Dave Brat credited his opposition to the Trade Promotion Authority (TPA) Republicans want to grant the president to his distrust of Obama and of GOP leaders in the Senate.

“The entire Democratic side is voting no, and the president is just going to bat for this thing, and so that makes you wonder,” Brat, who represents Virginia, said on The John Fredericks Show Friday. “What does he know that the Democrats don’t know?”

“Right? What’s he got in his mind down the pike that can be added to this thing?”

Obama says he needs TPA to clinch what could be the biggest trade deal in American history, the Trans Pacific Partnership. And Republican supporters are backing him up, saying TPA is crucial to future trade deals that would help the economy. (RELATED: Why Are Senate Republicans So Eager To Cede Their Trade Authority To Obama?)

TPA gives Congress more control in the negotiating stages of a trade deal, but once the president submits a deal to Congress, TPA severely restricts the Senate by forcing a vote without the chance for amendments or long debate. It also lowers the threshold to 51 votes, which is a drastic reduction from the 61 votes required for most legislation, or the 67 votes required for a treaty.

“I’m a total free trader,” Brat said. “It hurts my brain. I have constituents who I know need trade to take place, and so it hurts me, but the issue does come down to — do you trust the president and this process?”

“And the only out is they say, ‘Well you get a final up or down vote,’ Brat continued. “Well, even there, look at the doc fix. If both sides of leadership do an end run and they agree ahead of time to find to find 300 votes for, you know, $140 billion unpaid for on the doc fix, they can do the same kind of thing in the TPA and TPP.”

Congress recently passed a bipartisan “doc-fix” that solves a recurring problem in the way Medicare payments are made to doctors. But the Congressional Budget Office estimates the bill will add $141 billion to the federal deficits over the next decade. (RELATED: Rand Splits With Rubio, Cruz To Vote For Deficit Exploding Healthcare Bill)

“And then my vote is nullified,” Brat continued. “And up here you know how it works. There’s sort of a 90-10 proposition. If there’s 90 percent good stuff that both sides of leadership want and 10 percent is unconstitutional, ‘Well, that’s an unfortunate detail,’ but it passes.”

“And that’s not the way I operate. I operate on the fundamentals. The rule of law matters, the Constitution matters, the free market matters, telling the truth matters, and if any of those get violated, I’m a no.”

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