Jennifer Epstein writes at BloombergPolitics:

Over tea at Hillary Clinton’s Washington home in late 2014, Elizabeth Warren warned her host that when it comes to Wall Street, what mattered most was the people Clinton surrounded herself with.

Months later, as Clinton launched her presidential campaign, Gary Gensler, who had been a Goldman Sachs banker before he became a senior policy aide and Bob Rubin protégé during the deregulatory years of Bill Clinton’s Treasury Department, came on board, in part to serve as a driving force behind her economic-policy shop. Remarkably, Warren would be one of his strongest supporters.

The deeper explanation is that Gensler is a financial-policy unicorn—a deregulator turned reformer. As head of the Commodity Futures Trading Commission, Gensler became known as one of President Barack Obama’s toughest regulators, willing to buck his friends and former colleagues to tighten rules on the $400 trillion swaps market following the 2008 crisis. His name became an expletive to many on Wall Street, to the delight of Warren and her allies.

 Now, Gensler (along with Mandy Grunwald, who works with both women) is a central conduit between Warren and Clinton. “Gary is tough, smart, and principled, and he really understands what it takes to make our economy work better for hardworking families. During his time at the CFTC, he showed that he is willing to take on the big banks and fight to make our financial system safer,” said Warren, who met with Clinton last week after endorsing the presumptive Democratic nominee. “I really respect him.”

That doesn’t mean that Gensler’s history doesn’t continue to shadow him—along with an old adversary, Bernie Sanders. “Unfortunately,” said Warren Gunnels, Sanders’ top policy adviser in the Senate and on his campaign, “Gary Gensler still has not learned the lessons of the late ’90s and of deregulating Wall Street.”

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