The most comprehensive investigation of the gasoline market in 16 years will delve into the factors that influence prices throughout the...

The most comprehensive investigation of the gasoline market in 16 years will delve into the factors that influence prices throughout the state.

Three state departments — the Attorney General’s Office, the Governor’s Office and the Department of Community, Trade and Economic Development — are teaming up to head the effort.

“Washington consumers frequently wonder why gas prices are consistently higher in some areas of the state than others,” said Attorney General Rob McKenna.

Average regular gas prices per gallon Monday ranged from $3.23 in Bellingham to $3.18 in Seattle to $2.98 in Spokane.

The state expects to publish findings from the first phase of the investigation in July and will hold a series of public forums on the gas-price issue this fall.

The first part of the study will analyze factors that affect pricing patterns in the state, while the second part will look at any market anomalies that are identified.

The state agencies have agreed to hire a University of Washington economist experienced in the state’s petroleum industry.

What you pay at the pump

Quarterly pricing report

The attorney general’s Antitrust Division collects and analyzes gas-pricing data every month and publishes a quarterly gasoline report that helps explain factors that affect gasoline prices in the state. The report is available at www.atg.wa.gov/Antitrust/GasPrices/GasolineReport.aspx.

Reporting what you see

Consumers who have evidence of price fixing or other antitrust violations can file a report on the attorney general’s Web site, www.atg.wa.gov/Antitrust/default.aspx, or call the Consumer Protection Division at 1-800-551-4636.

“Should our research uncover price fixing or other violations of our state’s consumer-protection or antitrust laws, the Attorney General’s Office stands ready to take enforcement action,” McKenna said in a prepared statement. He asks consumers to alert his office if they overhear a conversation that suggests rival businesses intend to fix or manipulate prices, or if they spot prices that seem out of the ordinary and can’t be explained.

The last comprehensive study on Washington gas prices was published in July 1991. In that study, the state Energy Office collected data from 51 cities throughout the state, representing 750 gasoline stations, 10 refiners and 131 gasoline wholesalers.

The study found significant differences in gasoline prices from city to city in Washington.

Susan Gilmore: 206-464-2054 or sgilmore@seattletimes.com