Of all the partners in the homeownership push, no industry contributed more to the corruption of the lending process than Wall Street. If mortgage originators like NovaStar or Countrywide Financial were the equivalent of drug pushers hanging around a schoolyard and the ratings agencies were the narcotics cops looking the other way, brokerage firms providing capital to the anything-goes lenders were the overseers of the cartel.
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It was a colossal breakdown in the duty Wall Street owed to its investing customers.
Years after the meltdown, investors began to understand how badly they'd been burned by Bear Stearns, Merrill Lynch, Lehman Brothers, Deutsche Bank, Greenwich Capital, Morgan Stanley, Goldman Sachs, and other smaller firms. Lawsuits against these firms alleging a dereliction of duty started cropping up in 2010 as investors began to realize that Wall Street's secret loan assessments had identified severe problems in mortgages well before they stopped selling them.
Unlike many other firms, Goldman Sachs went negative on the mortgage market in the fall of 2006, well before others in its industry. Using its own money, the firm began amassing major bets against the same dubious loans it was peddling to investors at that time. Goldman, therefore, profited immensely from the losses its clients absorbed, losses its own practices helped to create.
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Wall Street had financed questionable mortgages before, of course. But it was during the mania's climactic period of 2005 and 2006 that these firms' activities as the primary enablers to freewheeling lenders really went viral. No longer were the firms simply supplying capital to lenders trying to meet housing demand across America. Now Wall Street was supplying money to companies making increasingly poisonous loans to people with no ability to repay them. And the firms knew precisely what they were doing.
http://www.huffingtonpost.com/2011/05/23/gretchen-morgenson-reckless-endangerment_n_864841.html