The Supreme Court's current term is already sure to be an big one for environmental law. Two major Clean Air Act cases, Massachusetts v. EPA and Environmental Defense v. Duke Energy, should yield important environmental decisions and more may be on the way. As Marty Lederman details on SCOTUSBlog, the Solicitor General has recently filed petitions for certiorari in four environmental cases, including another Clean Air Act case, and has acquiesced to certiorari in two others. Adding just a few of these cases to the Court's dockets would make this a truly major environmental term.

Yesterday the Supreme Court granted cert in another significant environmental law case — actually two combined cases, National Association of Home Builders v. Defenders of Wildlife and EPA v. Defenders of Wildlife — concerning the extent to which the Endangered Species Act (ESA) requires federal agencies to avoid actions that could harm endangered species when such a requirement could conflict with an agency's other statutory obligations. As Lyle Denniston notes on SCOTUSBlog:

The endangered species case grows out of a move by the state of Arizona to take over from EPA the program of regulating permits for discharge of pollutants under the Clean Water Act. The Court granted both cases, and added to the review the question of whether the EPA decision to transfer this permitting authority was wrongly based upon inconsistent views of the Endangered Species Act and, if so, whether the case should have been sent back to EPA for further review.

Here is the petition, opp, and reply brief.

MORE: The divided opinion of the U.S. Court of Appeals for the Ninth Circuit is here. The dissenting opinions from the denial of en banc review by Judges Kozinski and Kleinfeld, along with Judge Berzon's concurrence, are available here. The Environmental Law Institute's "Endangered Environmental Laws" program profiles the case here.

[NOTE: Links should be fixed now.]

UPDATE: Holly Doremus explains why this case "is potentially the most important ESA case the Court has heard since TVA v. Hill."