Appetizer

Passed in 1970, with significant amendments in 1977 and 1990, the Clean Air Act (CAA) has grown to be an 800-page statute. Under the CAA, the Environmental Protection Agency (EPA) sets national ambient air quality standards (NAAQS) that define how much of a pollutant can be in the air anywhere in the United States. States are required to meet those standards by creating their own, unique state implementation plans (SIPs). States must meet the NAAQS by CAA-specified deadlines. In addition to the NAAQS, the CAA also authorized the EPA to establish "technology-based standards" that set emission limits on the sources of pollution.

As originally passed, the CAA was a classic command-and-control approach to environmental regulation. Thirty-five years ago command-and-control regulations may have been the only thing that could clean up toxic waste dumps and flammable rivers, but today such regulations are too expensive, too inefficient, and too inflexible. Market-based regulations offer less costly and more efficient tools to keep our air clean. Amendments to the CAA, in 1990, added market-based regulation of two pollutants, and have proven to effectively protect the environment at significantly lower costs.

In 2007, the United States Supreme Court ruled in a 5-4 decision that carbon dioxide (CO2) and other greenhouse gasses are pollutants that cause global warming. This decision further expanded the role of the EPA under the Clean Air Act and brought many more industries and activities under the EPA's jurisdiction.