Californians have been paying a roughly 20 cent "mystery surcharge" on gasoline for the last 4 years and a coalition of lawmakers is asking the attorney general to find out why.
The added 20 cents a gallon has reportedly cost drivers more than $17 billion.
The hidden charge was first identified in a 2017 report on the state’s high gasoline prices .
California drivers regularly pay some of the highest gasoline prices in the nation, according to AAA .
UC Berkeley economist Severin Borenstein, a lead author of the report, says the mystery charge showed up just a few months after the researchers started their work in 2014 studying the state's high gas prices.
A February 2015 explosion at Exxon Mobil's refinery in Torrance caused a major disruption in California's oil market, causing prices to spike while the refinery shut down but once it got back online prices stayed high.
This 'could be because refineries are colluding to pocket the extra profit,' Borenstein said. 19 legislators, majority from the Bay Area, sent a letter Monday requesting the Department of Justice to investigate.
Read more at the Mercury News .
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