Barack Obama says critics of the trade deal, TPP, should look at the facts. Elizabeth Warren fired back on The Rachel Maddow Show last night, accusing the White House of keeping those very facts a secret.

Warren's appearance on MSNBC was in response to the president's own MSNBC segment on Tuesday, in which he called Warren's TPP stance "wrong."

"When you hear folks make a lot of suggestions about how bad this trade deal is, when you dig into the facts, they are wrong," he said.

Warren's response gets at one of the deepest criticisms of trade deals generally: they are largely negotiated in private. As a senator, Warren can review text as it's negotiated. But she can't share what's happening with the public.

"It's the case that the president says he wants the American people to judge this deal based on the facts, but to do that, he's got to make the deal public. Otherwise the American people can't judge it on the facts. He won't put the facts out there," she said. She added that Congress shouldn't "grease the skids" of such a secretive deal by approving fast-track legislation, under which Congress would give the 12 TPP nations' agreed-upon treaty text an up-or-down vote, with no amendments.

Warren's comments came just hours after the Senate Finance Committee approved fast-track legislation, however, putting the administration one step closer to getting its massive trade deal passed.

Warren is perhaps the most vocal of Obama's TPP opposition in Congress, much of which is coming from members of his own party — progressive Congress members including Warren, as well as Sherrod Brown and Bernie Sanders.

Why the administration keeps the text secret

Trade deals are negotiated unlike normal US legislation. The deal is supposed to be kept secret during the process for strategic reasons. From the US's perspective, it lets negotiators go into the room without showing their hand.

But of course, nothing is locked in a vault. Early, leaked drafts suggest that the deal is tipped in favor of big corporations and other groups with specific interests. That looks bad for the White House, and it has substantive problems, too.

This deal is sweeping, covering a wide variety of areas like intellectual property and environmental concerns, and it won't have the benefit of public scrutiny before the nations agree on it. Ohio State law professor Margot Kaminski put it best at the New York Times the other week: "Because the negotiating process combines a general shield from the public with privileged access for industry advisers, the substance of American free trade agreements does not represent truly national interests. "

The dilemma on fast-track

If Congress passes fast-track legislation, it means that once the administration negotiates a deal, Congress can only give it an up-or-down vote, without making any amendments.

There is a good argument for fast-track — namely, that it's simply too hard to negotiate a deal with other countries if they know the US could change it after the fact. But as with secrecy, there are also great arguments against it — that it won't allow Americans' elected representatives much of a say in how that already-secretly-negotiated agreement eventually looks.

To be fair, we do have some information on what's in the TPP: the USTR has published its TPP negotiating objectives. And the administration often points to its nearly 1,700 TPP meetings on Capitol Hill, a way of emphasizing that the deal isn't secret to Congress members themselves.

And the administration also emphasizes that, should Congress pass fast-track authority, the deal will be public for 60 days, and Congress can only vote on it 30 days after that period has ended, as the New York Times reports.

But combine the secrecy and fast-track, and you can see why some members of Congress are concerned. There are likely to be things that benefit Americans in the TPP — American farmers, for example, are excited about having more open markets for their goods. But leaked chapters indicate that parts could hurt lots of people, like if pharmaceutical companies make it more difficult to produce generic drugs. Whatever good and bad things the closed-door negotiations have combined into a trade pact, fast-track will require Congress to vote up or down all at once, taking the bad with the good.

This isn't to say a trade pact won't be a compromise — that comes with pretty much any international agreement. But TPP as the Obama administration wants it will involve layering together two processes that go against the normal, transparent way of passing laws in the US. That's the uncomfortable problem at the center of the TPP fight, and it's a big part of why Obama finds himself at odds with his own party.

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