Jan. 30, 2019—The Colorado Automobile Dealers Association sued a state agency Tuesday, seeking to overturn recently adopted vehicle emission regulations based on California standards, according to the Colorado Springs Gazette.

The dealership group charges that the state’s Air Quality Control Commission violated constitutional requirements and skipped steps in the rule-making process by reaching a predetermined outcome based on an executive order issued last year by then-Gov. John Hickenlooper. In November, Colorado adopted vehicle emission rules incorporating California standards, after an order by Hickenlooper aimed at reducing the state’s greenhouse gas emissions.

Citing a figure produced by the Trump administration, the dealers said the rule would add more than $2,000 average to the cost of new vehicles in Colorado, according to the report.