TAX THE EXTERNALITIES:

[A] 2011 paper by Patrick Bolton, Tano Santos, and José Scheinkman argues that a significant amount of speculation and deal-making is pure rent-seeking. In other words, it is wasteful activity that achieves nothing more than enabling the collection of rents on items that might otherwise be free.

The classic example of rent-seeking is that of a feudal lord who installs a chain across a river that flows through his land and then hires a collector to charge passing boats a fee (or rent of the section of the river for a few minutes) to lower the chain. There is nothing productive about the chain or the collector. The lord has made no improvements to the river and is helping nobody in any way, directly or indirectly, except himself. All he is doing is finding a way to make money from something that used to be free. If enough lords along the river follow suit, its use may be severely curtailed.

Those in "other finance" often engage in similar behavior. They skim the best business deals, creating a "negative externality" on those who are not party to them. If the bad assets that they reject - for example, the subprime mortgage securities that fueled the 2008 financial crisis - are created anyway and foisted on less knowledgeable investors, financiers contribute no more to society than a lord who installs a chain across a river.

In a forthcoming paper, Patrick Bolton extends this view to look at bankers and at the Glass-Steagall Act, which forbade commercial banks from engaging in a wide variety of activities classified as "investment banking." Ever since the Gramm-Leach-Bliley Act of 1999 repealed Glass-Steagall, bankers have acted increasingly like feudal lords. The Dodd-Frank Act of 2010 introduced a measure somewhat similar to the Glass-Steagall prohibition by imposing the Volcker Rule, which bars proprietary trading by commercial banks, but much more could be done.

To many observers, Glass-Steagall made no sense. Why shouldn't banks be allowed to engage in any business they want, at least as long as we have regulators to ensure that the banks' activities do not jeopardize the entire financial infrastructure?

In fact, the main advantages of the original Glass-Steagall Act may have been more sociological than technical, changing the business culture and environment in subtle ways. By keeping the deal-making business separate, banks may have focused more on their traditional core business.

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