After the Wall Street crash of 1929, it took four years before Congress passed the Glass-Steagall act, which split commercial banking from securities dealing. (Before the legislation bank deposits were frequently diverted in support of new issues by commercial bankers' investment-banking colleagues.) Other restrictive rules continued to be made until 1940.

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Whereas, the Glass-Steagall Act unfairly limited them to retail and commercial banking.

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Merrill was one of the leading campaigners for the abolition of the Glass-Steagall act that kept investment banks out of commercial banking.

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But this influence did not stop Congress passing the Dodd-Frank act, has yet to stop Britain's planned divide between commercial and investment banking, and has not held up a host of new EU regulations.

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