Was inequality to blame for the financial crisis? A paper (pdf) by Michael Bordo and Christopher Meissner suggests not. They point out that, in developed countries since the 1920s, the sort of credit booms that lead to crises have not generally been associated with rising inequality. This casts doubt upon Raghuram Rajan's idea that rising inequality led to the crisis by encouraging lax regulation of lending to low-income households; though he is not alone (pdf) in suggesting such a link.

One can question the relevance of Bordo and Meissner's evidence. The fact that crises are not often preceded by rising inequality does not disprove that inequality - along with other mechanisms - had a role in this particular crisis.

And there are two other mechanisms through which inequality might have precipitated the crisis:

- Insofar as rising inequality in the 00s was correlated with a rise in wages in the financial sector relative to other industries, it attracted 'talent' into banking. And this contributed to its downfall, because 'talent' produces not stability but rent-seeking and overconfidence. Remember - banks survived for decades by employing doddering Captain Mainwarings but collapsed soon after hiring physics PhDs.

- One contributor to bank collapses was inequality of power. Top-down management structures produce bosses who combine domineering arrogance with ignorance. As Julian Birkinshaw has said (pdf), the management model in investment banks was one in which 'Aggressive and intimidating behaviour is tolerated; effective teamwork and sharing of ideas are rare.'

And even if inequality did not cause the crisis, it is correlated with it. The same growth (pdf) of Asian economies that gave us an excess supply of cheap labour which depressed unskilled wages in the west also gave us the savings glut that produced the housing boom and malinvestments in mortgage derivatives.

But does it much matter whether income inequality contributed to the crisis or not? The Left argued that high inequality was a bad thing long before the crisis, for intrinsic as well as instrumental reasons. Those arguments are as strong (or as weak!) as they ever have been.