Whitman v. Am. Trucking Ass'n, Inc.

The Clean Environment Air Act was under question because it set an ambiguous line for the EPA to set primary ambient air quality standards with an adequate margin of safety, with disregard to the costs of such standards.

The lower court said that the EPA could avoid the unconstitutional delegation by adopting a restrictive construction of the granted power.

Whether Congress can confer vague legislative power to a federal agency.

No.

Reversed.

When Congress confers legislative authority upon an agency Congress must lay down by legislative act an intelligible principle to which the person is directed to conform.

An agency cannot cure an unconstitutionally delegated standard by declining to exercise that power.

The requisite standards to protect public health fits comfortably within the scope of discretion permitted by precedent.