This Day In Purple —Bipartisan Amendments 1970 Clean Air Act

September 22, 2020

As another congressional term comes toward a close without major progress, it is remarkable to look back five decades to a time of bipartisan consensus on environment issues.  

On This Day in Purple fifty years ago (September 22, 1970),  the U.S. Senate passed a series of important amendments to the 1963 Clean Air Act, expanding federal oversight and regulation of automobile and airplane emissions and establishing the National Ambient Air Quality Standards (NAAQS).  

The Senate vote on these amendments was a remarkably bipartisan 73 in favor, none opposed, and 27 abstentions. A total of 31 Republican Senators thus voted in favor of stricter environmental standards enforced at the Federal level – virtually unthinkable in today’s polarized Senate. 

The spirit of these measures was originally proposed by Republican President Richard Nixon earlier that year. Nixon reacted to growing public pressure following both the 1969 Santa Barbara Oil Spill in his home state of California and an enormous increase in automobile emissions and smog in urban areas. His ambitious agenda, which would culminate in the creation of the Environmental Protection Agency late in 1970, was quickly incorporated into a bipartisan congressional agenda that became one of the most effective federal environmental policies to date.

The Senate’s bipartisan Environment and Public Works Committee, led by Senator Edmund Muskie (D-ME), worked to integrate Nixon’s goals into practicable policies through the spring and summer of 1970. Sen. J. Caleb Boggs (R-DE) sat on the subcommittee on Public Works and co-sponsored the bill. Years, if not decades ahead of other policymakers on the issue climate change, Boggs presciently stated: 

 “Air pollution alters climate and may produce global changes in temperature. The addition of particulates and carbon dioxide in the atmosphere could have dramatic and long-term effects on world climate.”

After months of deliberation and negotiations with automobile manufacturers in Michigan, Muskie and his colleagues brought the amendments to the Senate floor for a  successful vote on September 22, 1970. After passage, Muskie remarked

“After all these hundreds of hours covering weeks and months of deliberations, all those Senators – obviously of widely varying political philosophies – voted unanimously to recommend to the Senate and Congress the passage of this bill, the goals it establishes, the sense of urgency it incorporates, and the program for meeting the problem. I cannot think of a major piece of domestic legislation that has had such complete committee support from that spectrum of opinion. There was no doubt in the minds of any of them about supporting it.” 

The Clean Air Act amendments would go through another round of deliberations and adjustments in both houses of Congress later that fall. But a strict regulatory framework and significant budgetary allocation remained at the heart of the final bill. President Nixon signed the Clean Air Act into law on December 31, 1970


“Text of the President’s Message to Congress Proposing Action Against Pollution” (2/11/70). The New York Times.

“Study finds peril in car fume level” (3/30/70). The New York Times.

“Public Law 91-604” (12/31/70). 

Congressional Record: Senate (9/22/70) 


In 1986, 34 Democratic and 29 Republican Senators signed the Immigration Reform and Control Act, creating a citizenship path for illegal immigrants while making it a Federal crime to employ illegal workers. The House also voted in favor, 238 to 173. The bill was signed into law on November 6, 1986.

In 1972, 17 Republican Senators joined 35 Democratic Senators to override the Nixon Administration veto of the Clean Water Act, a landmark piece of environmental legislation. The House override vote was 247 to 23, including 96 Republicans and 151 Democrats in the majority.

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