The feds suspect something more than supply and demand may be at play at the gas pump. 

An investigation into possible price-fixing is underway as the Federal Trade Commission explores whether the oil industry colluded to keep gasoline prices high--and whether the industry lied about doing so.

The FTC points out that pump prices jumped to a nationwide average of $4.00/gallon this spring, but refiners were only producing at 82% of capacity.  Demand for and price Gasoline prices and demand have eased since May, though production was higher than a year ago.

One industry trade group says the probe is a waste of tax dollars.

"Dozens of investigations of gasoline price fixing over the years have generated plenty of headlines and political hyperbole, but have failed again and again to find any evidence of wrongdoing. This will happen again," says a statement by Charles Drevna, head of the National Petrochemical & Refiners Association.

The probe is looking at producers, refiners, transporters, marketers and traders.