Marsh v. Oregon Natural Resources Council 490 U.S. 360 (1989)
The US Army Corps of Engineers was building three dams on
a river in Oregon.
Pursuant to the National Environmental Protection Act
(NEPA), the Corps prepared an Environmental Impact Statement (EIS).
After the final EIS had been completed, new studied were
published indicating that the projected would have a more adverse impact
than previously thought.
The Corps decided not to prepare a supplemental EIS to
consider this new information.
NEPA does not explicitly address what to do in
The Council on Environmental Quality (CEQ) had
interpreted NEPA to require a supplemental EIS when there is
"significant new circumstances or information relevant to
environmental concerns and bearing on the proposed action or its
The Corps own regulations require a supplemental EIS
when there is "new significant impact information, criteria, or
circumstances relevant to environmental considerations impacting on the
recommended plan or proposed action."
Marsh sued to stop the project on the grounds that the EIS
was not adequate.
Marsh argued that since new information had come to
light, the original EIS was flawed and needed to be updated.
The Trial Court found for the Corps. Marsh appealed.
The Appellate Court reversed and issued an injunction.
The Corps appealed.
The Appellate Court found that the Corps had failed to
evaluate the new information with sufficient care and therefore had
failed to meet the requirements of NEPA.
The US Supreme Court reversed the Appellate Court and
allowed the project to go forward without the need for a supplemental EIS.
The US Supreme Court found that the decision to prepare a
supplemental EIS is similar to the decision to prepare an EIS in the
The Court found that judicial review of agency decisions
is limited to whether they were 'arbitrary or capricious'.
Basically, the Court was saying that whether the new
information was 'significant' was a scientific fact that was beyond the
scope of a court to review. Deference should be given to the scientists
in the agency to decide what constitutes a significant change.