State officials should send independent inspectors to verify oil company claims that the shutdown of two refineries in California were really necessary, says the group called Consumer Watchdog of Santa Monica.

In a letter Wednesday to the governor, the state attorney general and lawmakers, Liza Tucker and Cody Rosenfield of Consumer Watchdog say they want to know if the companies “are telling the truth.”

They also call for a law that would ensure independent, on-site refinery investigations whenever a shutdown occurs in order to assure the public that outages are justified.

A Martinez refinery was shut down on Feb. 6 and one in Torrance went offline on Feb. 16.

Since Feb. 6, gasoline prices have jumped 27 cents a gallon in California, on average, while the U.S. average has jumped only a dime a gallon. The refineries say that the shutdowns were caused by safety concerns during a steelworkers' strike and by a mechanical failure, respectively.

"Unfortunately, California refineries have a history of trying to manipulate gas prices by restricting supply," the consumer advocates write.