The Supreme Court recently halted implementation of the Environmental Protection Agency’s existing power plant greenhouse gas rule until court challenges are resolved. The 5-4 decision freezes implementation of the existing source performance standards. The stay will stop compliance activities in many states that oppose the rule, providing hope for an eventual court victory or a new administration that will scrap the policy.
 
The decision could also undercut the administration’s recent pledge under the United Nations climate agreement reached in Paris, given that the ESPS was a cornerstone policy underpinning that pledge.