In his debate with Elizabeth Warren last night, Senator Scott Brown struck an odd pose—as a Wall Street reformer. Just as Mitt Romney dishonestly did during last week’s presidential debate, Brown was attempting to re-upholster an ugly record of helping out the country’s largest financial institutions.

When Warren brought up her brainchild, the Consumer Financial Protection Bureau, Brown eagerly attempted to hop on the bandwagon—drawing boos from the crowd:

Relevant transcript:

BROWN: Listen I commend you for your work on that. I voted for it, it never would have passed if I wasn’t the deciding vote on the financial reform. [boos] Senator Reed and I went in and actually put in a provision in there to protect our men and women service members who were going to be taken advantage of by the predatory lenders. So I commend you for that, and I’m glad I was able to help put it into effect.

Indeed, Brown was the deciding vote for financial reform. And he used it to win huge concessions for Wall Street before agreeing to vote yes.

First, as has been widely reported, Brown maneuvered behind the scenes to force Democrats to strip a bank tax from the legislation that would have raised $19 billion to pay for implementation of Dodd-Frank. Only banks with assets over $50 billion would have been required to pay that tax—but Brown insisted it be taken out.

For posterity’s sake, I confirmed this today with Representative Barney Frank, the eponymous co-author of the legislation. “We needed to break the filibuster and he, Susan Collins and Olympia Snowe did make the difference,” Frank said. “The facts are, I got a call from Chris Dodd and Harry Reid—‘you gotta work with Brown, we need his vote.’ ”

The work involved scrapping the bank tax, Frank recalled. “They extracted a price for it. Twenty billion dollars off the backs of the banks and onto the taxpayers,” he said. “And frankly, for us, that would have set the precedent of [the cost of the regulation] being on the financial institutions. We were ready to go beyond that. We lost that and that was it.”

Brown also scored a series of exemptions in the legislation to the proposed Volcker Rule, which is intended to keep commercial banks from engaging in risky proprietary trades.

As he was doing this, money was “pouring in” to his campaign coffers from Wall Street, at a rate four times higher than what any other Republican Senator was seeing. (In fact, as a 2010 ThinkProgress analysis showed, Wall Street provided a significant eleventh-hour boost to his campaign, and Brown initially opposed financial reform before deciding to trade his vote for substantial reductions in the law’s reach).

So it takes some real “brass,” in the parlance of Bill Clinton, to fund your campaign with Wall Street dollars, given as a thank-you for weakening financial reform, and then turn around in the same campaign and ask for votes because you “helped put it in effect.”

For more political hypocrisy, see John Nichols take down Paul Ryan’s claim that he fights for auto workers.

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