State AG Database – Climate Change Mitigation

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The following is a list of major actions taken by state attorneys general to advance action on climate change mitigation and greenhouse gas emission reductions:


Lawsuits v. Federal Government

Massachusetts v. EPA (2007): Multi-state challenge to EPA denial of petition to regulate greenhouse gas emissions from motor vehicles under Clean Air Act.


Lawsuits v. Private Actors

Settlement, Connecticut v. Hyundai Motor Co. (Conn. Super. Ct. 2016): Multi-state settlement of consumer-protection claims against car manufacturers that overstated their vehicles’ fuel efficiency.

American Electric Power v. Connecticut (2011): Federal common law nuisance claim against five major electric power companies for their contribution to climate change through greenhouse gas emissions.


Defense of Federal Standards

North Dakota v. United States Environmental Protection Agency (D.C. Cir. 2015): Multiple states filed amicus brief in support of EPA in litigation challenging New Source Performance Standards (NSPS) regulating carbon dioxide emissions from new and modified power plants

West Virginia v. EPA (D.C. Cir. 2015): Multi-state intervention to join EPA’s defense of Clean Power Plan against challenge mounted by other states and industry petitioners.

Utility Air Regulatory Group v. EPA (2014): Multiple states intervened in lawsuit to defend EPA rules concerning regulation of greenhouse gas emissions from stationary and mobile sources.


Defense of State Standards

Defense of California Feed-in-Tariff Program (2009): California AG filed brief with the California Public Utility Commission defending the state’s authority to use feed-in tariffs.

Central Valley Chrysler-Jeep, Inc. v. Goldstene (2007): State AGs intervened in lawsuit to defend California’s greenhouse gas emission standards for motor vehicles against challenge alleging that the standards are preempted by the Energy Policy and Conservation Act (EPCA).


Amicus Briefs

North Dakota v. United States Environmental Protection Agency (D.C. Cir. 2015): Multiple states filed amicus brief in support of EPA in litigation challenging New Source Performance Standards (NSPS) regulating carbon dioxide emissions from new and modified power plants


Administrative Proceedings

Comments on Tennessee Pipeline Gas Go. Northeast Energy Direct Project (2015): Massachusetts AG submitted comments to Federal Energy Regulatory Commission and a study opposing a proposed natural gas pipeline that would have run through New England.

Agreement for DOE to Update Energy Efficiency Standards (2013): Multi-state coalition reached agreement with U.S Department of Energy establishing timetable for updating federal efficiency standards for energy-intensive consumer products.

Defense of California Feed-in-Tariff Program (2009): California AG filed brief with the California Public Utility Commission defending the state’s authority to use feed-in tariffs.


Other Interventions

Green 20 State AG Coalition (2016): Group of 17 state AGs and Former Vice President Al Gore announced a coalition of states committed to taking creative steps to combat climate change, including investigations into fossil fuel companies and climate-related disclosures.