This IGM poll of leading economists on the importance of various factors in the financial crisis of 2008 provides interesting results. The poll lists 12 factors, and all of them receive at least some positive weight. In fact, this under-estimates the complexity of the causal mechanisms, because some of the factors are themselves multi-faceted. For example, the first factor, “flawed financial sector regulation and supervision,” could mean many different things to many different people. It could mean the repeal of Glass-Steagall (a favorite among non-economists on the left) or it could mean the Basel accords (one of my personal favorites).
Overall, I think it vindicates the broad, multi-causal approach that I took in Not What they Had in Mind.