This afternoon, the U.S. Senate voted down a resolution sponsored by Senator Lisa Murkowski (R-AK) that would have prevented the U.S. Environmental Protection Agency (EPA) from regulating emissions of greenhouse gases under the federal Clean Air Act.

By a largely party-line vote of 53-47, Democrats were successful in defeating the measure, which intended to voice Congress’ disapproval of the finding that greenhouse gas emissions are an endangerment to human health, and therefore effectively prevent the EPA from moving ahead with regulation of carbon.

After a Supreme Court ruling in 2007 affirming that greenhouse gas emissions are a criteria pollutant covered under the Clean Air Act, the Obama Administration’s EPA has been pursuing incremental regulation of these emissions. In part, this regulatory action by the EPA has served as an impetus in Congress to enact their own approach to limiting greenhouse gas emissions.

President Obama had threatened to veto the measure, and Democratic leaders in the House were confident the measure would not pass their body. However, the vote presented  a considerable leadership challenge on the climate change issue to Democrats. There was political pressure on Senators to support the resolution as a way to voice their opposition to EPA regulation of carbon AND voice their preference for a legislative solution. The latest legislative vehicle is a comprehensive energy and climate bill authored by Senators John Kerry (D-MA) and Joseph Lieberman (I-CT).

In the end, the vote – and the result – highlight the acute need for Congress to act on implementing climate change legislation with provisions for a market-based, flexible compliance mechanism. Such legislation will offer business regulatory clarity, and the carbon market components would enable emissions to be reduced faster, at less cost, and with greater environmental benefits.