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The Past, Present, and Future of the Clean Air Act

Updated: Oct 4, 2022

“I think that 1970 will be known as the year of the beginning, in which we really began to move on the problems of clean air and clean water and open spaces for the future generations of America.” - Richard Nixon

What is the Clean Air Act?

The Clean Air Act (CAA) is one of the most significant pieces of environmental legislation in the United States. It plays a central role in limiting air pollution and penalizing polluters. However, it’s important to remember that it didn’t start out that way. The CAA was first signed into law in 1963, at a time when regulating air pollution was solely the responsibility of state and local governments. The original CAA authorized the federal government to study air pollution, but it suffered from a major flaw: states were not required to regulate air pollution. This flaw was fixed when CAA was amended in 1970. The amendments gave the newly-created Environmental Protection Agency (EPA) the responsibility to set national air quality standards that limited the emissions of harmful pollutants and required states to develop plans to implement those standards. The CAA was amended in 1977 which added provisions for the Prevention of Significant Deterioration of air quality. The CAA was amended once again in 1990 to authorize new programs to control acid rain, restricting toxic air pollutants and expanded research programs.

A Bipartisan Achievement

It might come as a surprise today that it was a Republican president, Richard Nixon, who signed the amendments to CAA into law, but he came into office just as the environmentalist movement was gaining steam. Inspired by books like Rachel Carson’s Silent Spring, and repulsed by environmental disasters such as a major California oil spill that occurred less than a month into Nixon’s presidency, Americans demanded action from their leaders to protect the environment. Nixon also feared that his likely opponent in the 1972 election, Ed Muskie, would use his own environmentalist credentials to win over voters. Muskie had spent much of the previous decade using his platform as a senator to call for stricter environmental legislation and took the lead in getting the CAA amendments through the Senate. Nixon’s own desire to one-up his opponents combined with the groundswell of environmentalism culminated late in 1970, when Nixon signed the amendments into law. Muskie was not invited to the signing ceremony.

Since then, the CAA has been amended twice more: once in 1977 by Jimmy Carter (Democrat) and again in 1990 by George H.W. Bush (a Republican). Both times, the amendments extended the legislative power of the CAA, with the 1990 amendments in particular increasing the federal government’s authority and responsibility in enforcing new environmental laws. It seems almost unimaginable today, but up until the last decade, environmental protection laws and strong government regulation have enjoyed widespread bipartisan support.

Keeping Score

Since taking office in 2017, President Donald Trump has reversed nearly 100 environmental regulations. Andrew Wheeler, the man he appointed to run the EPA, was known for his legal work for a coal magnate and his opposition to coal regulations during Obama’s presidency. Wheeler’s predecessor, Scott Pruitt, accepted hundreds of thousands of dollars from fossil fuel companies when running for political office. The Clean Air Act has been among the many environmental regulations that Trump has sought to roll back.

One major change Trump has proposed to the CAA prevents the EPA from including the indirect benefits of reducing air pollution in its cost-benefit calculations. According to an EPA report from 2011, the amendments to the Clean Air Act have saved over 200,000 lives per year and delivered benefits equivalent to 42 times their costs. It is for this reason that opponents of the Clean Air Act are so keen to change the way costs and benefits are calculated. For example, the regulations that limit the particulate matter that accompanies mercury pollution have been estimated to prevent 130,000 asthma attacks per year. Because these asthma attacks cannot be directly attributed to the emission of mercury, they would no longer be counted as a benefit.

Trump’s administration also finds itself at odds against state governments which want the CAA to be enforced. Two states (New York and Connecticut) are currently suing him in federal court alleging that his administration has failed to enforce the CAA by allowing neighboring states to pump air pollution into their own states. More recently, 24 states are suing Trump for not upholding the CAA. One center of resistance to Trump’s attempts to relax air quality standards has been California (which would rank as the fifth-largest economy in the world if it were its own country), a state that has long exceeded the air quality standards mandated by the Clean Air Act.

Lessons Learned

The most important lesson from the passage of the 1970 amendments to the Clean Air Act is that the amendments were signed into law because of the popularity of the environmentalist movement. They wouldn’t have stood a chance a decade earlier when most Americans were uninterested in environmental concerns and the president had nothing to gain politically from signing them. Legislation to deal with climate change today might benefit from the fact that the public is more concerned by climate change than it has ever been. But unlike in 1970, the concern about climate change today is a more partisan issue. The Republican Party that helped to give America clean air standards is now led by a man who believes climate change to be a Chinese hoax. If concern over climate change remains a partisan phenomenon, it will be difficult for a future Democratic president to win over enough senators and representatives to support meaningful climate change legislation.

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