This of course does not mean that financial instrumentation, speculation or other forces of the financial markets did not contribute to the crisis, but it is a distinct claim from the one made by those proposing that they caused the crisis single-handedly.
By sheer accident, looking through some old research papers, I came across this study from the ECB: Lombardi, Marco J. and Van Robays, Ine, Do Financial Investors Destabilize the Oil Price? (May 20, 2011). ECB Working Paper No. 1346. Available at SSRN: http://ssrn.com/abstract=1847503
The study looks into the large oil price fluctuations that were observed in the recent years. In particular, the study considers the role of financial activities in the determination of oil prices.
Per study (emphasis is mine):
"The oil futures market has indeed become increasingly liquid, and the activity of agents that do not deal with physical oil, the so-called non-commercials, has greatly increased. This led some to hypothesize that inflows of financial investors in the futures market may have pushed oil prices above the level warranted by fundamental forces of supply and demand, whereas others argue that the impact of financial activity on the oil spot market is negligible or non-existent beyond the very short term."
- Destabilizing financial shock is identified as one that creates "a deviation from the no-arbitrage condition, thereby ...driving oil futures prices away from the levels justified by oil market fundamentals.
- Stabilizing financial activity is defined as "driven by changes in oil supply and demand-side fundamentals".
- an oil supply shock
- an oil demand shock driven by economic activity
- an oil-specific demand shock which captures changes in oil demand other than those caused by economic activity, and
- a destabilizing financial shock (such as a spike in speculative activity).
- Financial activity in the futures market can significantly affect oil prices in the spot market, although only in the short run.
- The destabilizing financial shock (speculation) only explains about 10 percent of the total variability in oil prices.
- Shocks to fundamentals "are clearly more important over our sample. Indeed, looking at specific points in time, the gradual run-up in oil prices between 2002 and the summer of 2008 was mainly driven by a series of stronger-than-expected oil demand shocks on the back of booming economic activity, in combination with an increasingly tight oil supply from mid 2004 on. Strong demand-side growth together with stagnating supply were also the main driving factors behind the surge in oil prices in 2007-mid 2008, and the drop in oil prices in the second half of 2008 can be mainly explained by a substantial fallback in economic activity following the financial crisis and the associated decline in global oil demand. Since the beginning of 2009, rising oil demand on the back of a recovering global economy also drove most of the recovery in oil prices."