Texas has filed the opening brief in a legal challenge it and eight other states are making to the Environmental Protection Agency's "tailpipe rule."

That rule aims to limit greenhouse gas emissions from motor vehicles. The brief filed by the Texas attorney general's office calls the rule "arbitrary" and exceeds the EPA's authority under the federal Clean Air Act.

The brief was filed on behalf of Texas, Mississippi, Alabama, Georgia, South Carolina, Virginia, Nebraska, South Dakota and North Dakota.

In a statement Monday, EPA spokesman Brendan Gilfillan defended the rule as a cost-saving measure for consumers that will also reduce air pollution and U.S. dependence on oil imports.

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