Environmental Defense Fund v. Colorado Department of Public Health

The Colorado Court of Appeals found that Colorado state agencies’ actions to implement 2019 climate change legislation were consistent with the duties imposed by a provision of the law that required publication of proposed rules by July 1, 2020 “to implement measures that would cost-effectively allow the state to meet its greenhouse gas emission reduction goals.” Environmental groups contended that the provision required the agencies to promulgate regulations “sufficient” to meet greenhouse gas reduction goals articulated elsewhere in the statute. The appellate court found that the provision’s language was ambiguous and that the rest of the statute’s text, the larger statutory scheme, and legislative history supported an interpretation that the provision was focused on rulemaking related to data collection and greenhouse gas inventories that would enable future measures to achieve the reduction goals. The appellate court further found that the agencies had satisfied their duties under the statutory provision.