In anticipation of the U.S. adopting a cap-and-trade program for greenhouse gases (GHGs), Professor Coplan explores the implications that the public trust doctrine might have on such a program. Rooted in Roman law and the common law, the public trust doctrine declares that certain public resources, such as flowing water, shorelands, and the air, are held by the sovereign in trust for the public benefit and are not susceptible to private ownership.

Coplan suggests that a cap-and-trade program for GHGs can be found to implicate the public trust doctrine, because arguably the atmospheric climate system is a public trust resource and the allocation of tradable emissions rights subjects this resource to private ownership. Under the broadest conception of the public trust doctrine, the government is prohibited from alienating public trust resources; however, Coplan's analysis of U.S. public trust cases suggests that a milder version of the public trust doctrine operates in the U.S. today. Under this milder version, implementing a cap-and-trade system for greenhouse gases is permissible, but, Coplan argues, sustainability principles implicit in U.S. public trust doctrine require that the cap for such a program be set at or below scientifically proven sustainable limits on GHGs.

Given the uncertain future of international action on climate change following the Copenhagen Accord, it appears that domestic actions within the individual signatories to the Accord will have to take the initiative on international greenhouse gas ("GHG") mitigation. Within the United States, however, such domestic efforts have not fared well legislatively, with several bills currently stuck in various stages of the legislative process.

Hannah Chang offers a way out of this impasse by focusing on the legal options available to the President for enteringinto binding International agreements without the advice and consent of the Senate. Relying on the principles  of Presidential power set forth in Justice Jackson's Youngstown opinion, the President's relevant enumerated powers, and the historical practice of executive agreements, she suggests that the President can rely on his independent foreign affairs powers, together with authority derived from existing treaties and congressional delegations, to enter into binding international  agreements that could address certain aspects of the climate change problem even as we wait for domestic climate legislation to be enacted.