Susan Merrill, head of enforcement at the Financial Industry Regulatory Authority (FINRA), is quitting, The Wall Street Journal reports. The departure comes as the U.S. brokerage regulator faced criticism in 2008 and 2009 for not having policed financial firms closely, along with missing frauds such as the Bernard Madoff Ponzi scheme.

Merrill joined FINRA in 2007, when the National Association of Securities Dealers merged with the regulatory arm of the New York Stock Exchange (NYSE). Merrill, formerly a litigation partner at law firm, Davis Polk & Wardwell, was appointed by the NYSE in 2004 to help restore is regulation unit.

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