For climate change mitigation, bipartisan politics can work

In an increasingly polarized nation, cooperation across party lines is key to sustained climate mitigation in the United States, according to a new CIRES study. To sustain climate progress over decades, bipartisan cooperation on solutions like renewable energy or emissions reduction will be necessary, the authors say. 

“In the long run, climate change mitigation will only be successful with public and political unity behind it,” said Renae Marshall, former CIRES researcher, Ph.D. student at the University of California Santa Barbara, and lead on the study out now in the current issue of Climatic Change. “Our study found that bipartisanship can help create working climate mitigation strategies in state-level contexts.”  

Marshall and her coauthor Matt Burgess, CIRES Fellow and CU Boulder Assistant Professor in Environmental Studies and Economics, analyzed 418 state-government enacted bills and 450 failed bills aimed at reducing emissions from 2015 to 2020, to identify the political contexts in which they were passed or defeated. 

The duo found that even though two-thirds of the climate-related bills passed in Democrat-controlled legislatures, one-third passed in Republican-controlled legislatures.   

Additionally, about a third of all analyzed bills had cosponsors from both major parties, suggesting there are still opportunities for bipartisanship.

Marshall and Burgess found that bipartisan or Republican-led bills favored financial incentives for renewable energy, as well as legislation that expands consumer choices—whereas Democrat-led bills favored those that restricted choice, such as mandatory renewable energy and emissions standards. “Key bipartisan opportunities at the state level are policies that not only provide financial incentives (such as renewable energy system tax credits), but also have an element of expanding opportunities for businesses and consumers to take part in the renewable transition (creating new consumer protections and financing options or allowing new sources of energy to participate in the marketplace),” said Marshall.

For example: Georgia found success when the 2015 Solar Power Free-Market Finance Act lifted restrictions that had previously kept the solar market from growing by allowing individuals and businesses to participate in lease financing agreements.

More bipartisan bills were proposed in ‘divided’ states (like Kentucky or New Hampshire) compared to Democrat- or Republican-dominated states, the team said, suggesting that equal representation on both sides of the political spectrum creates a better environment for cooperation on climate bills. 

“The more polarized we get, the more of a barrier there is. Working together across party lines is the solution,” said Marshall. “Bipartisanship opens up new opportunities to find common ground and dive into sustained climate initiatives.” 

The study grew out of Marshall’s undergraduate Honors thesis in Environmental Studies at CU Boulder, which earned her recognition as the College of Arts and Sciences Outstanding Graduate in 2021.

“Bipartisanship has its challenges—but it’s worth it,” Burgess said. “Not only will more successful bipartisan bills increase the amount climate mitigation strategies put in place, bipartisanship in climate decisions might actually help shrink the political polarization in our country as a whole. Previous research has found that working towards shared goals reduces inter-group conflict.”