Speculation in the petroleum futures market was a major contributor to the rise in oil prices during 2008, according to Gary Gensler, chair of the Commodity Futures Trading Commission.

This is a reversal from a 2008 report by the Commodity Futures Trading Commission, which pointed to supply and demand as the cause of the run-up. Gensler said the Commission plans on changing the report, attributing the rise to speculative traders. Oil hit a high of $145 a barrel in July 2008, dropping to $33 a barrel by the end of the year.

The federal government "must seriously consider" regulating energy markets to curb speculation, Gensler said last week.

"This hearing is an opportunity to determine how speculative position limits could be used to address excessive speculation, not how we can eliminate speculation," Gensler said, opening the first of three days of meetings the agency is holding on whether to restrict the volume of trading.

The New York Times points out that industries that buy petroleum products, such as trucking and the airline industry, have blamed much of the oil price volatility on speculators -- purely financial traders who never actually take delivery of any petroleum products.

Much of the criticism has focused on exchange-traded index funds, said the Times, which are like index mutual funds but trade like stocks and allow investors to bet on rising energy prices.

(Read the New York Times report here.)