The mayors of hundreds of U.S. cities called on Congress this week to pass legislation to put a price on carbon emissions, citing the financial and social strains their communities are already experiencing because of climate change.

After some contention, they also voiced opposition to any congressional action that would limit cities' ability to sue fossil fuel companies for damage linked to climate change. That vote marked a stand by the mayors against one of the key policy trade-offs sought by big oil companies that have backed the idea of carbon pricing.

The carbon pricing resolution, introduced by Salt Lake City Mayor Jackie Biskupski, calls for a price "sufficient enough to reduce carbon emissions in line with ambitions detailed in the Paris Agreement on climate change."

"We need our elected leaders in Washington to do what many of us as mayors are already doing at home: Move swiftly to adopt policies to mitigate the effects of climate change and ensure the long-term health of our environment," Biskupski said in a statement.

Sign up for InsideClimate News Weekly Our stories. Your inbox. Every weekend.

The two resolutions were among a slew of climate-focused policy positions endorsed by the U.S. Conference of Mayors by voice vote as its annual meeting drew to a close Monday in Honolulu. The mayors also voted in support of a resolution endorsing the idea of a Green New Deal, called for Congress to adopt "a comprehensive national response" to climate change, and voted to oppose President Donald Trump's plan to freeze vehicle fuel economy standards.

The vote endorsing cities' right to sue over climate damages came after the two Republican mayors who served as chair and vice chair of the conference's environment committee, Francis Suarez of Miami and Bryan Barnett of Rochester Hills, Michigan, sought to put off a vote. But the proposed policy statement passed with strong support from mayors of other cities in Florida, where sea level rise is a growing risk, as well as in California, New York and Washington state. Barnett, the incoming president of the U.S. Conference of Mayors, stood at the meeting's final session to offer the resolution for a vote along with the entire package of climate policy position statements.

The resolution supports "cities' rights and efforts to mitigate climate change damages and protect taxpayers from related adaptation costs." It opposes any action by Congress or in state legislatures "to limit or eliminate cities' access to the courts by overriding existing laws or in any way giving fossil fuel companies immunity from lawsuits over climate change-related costs and damages."

Eight cities, six counties and one state (Rhode Island)—collectively representing approximately 15.4 million people or 4.7 percent of the U.S. population—have filed lawsuits over the past two years seeking to hold fossil fuel companies accountable for the costs of climate change, the resolution notes.

Elevating Cities' Climate Concerns

The U.S. Conference of Mayors includes the leaders of cities with populations greater than 30,000, about 1,400 cities. Although the conference—which dates back to the Great Depression—describes itself as non-partisan, it leans heavily Democratic, as do the urban areas that elected most of the mayors. Among the current mayors of the nation's 100 largest cities, 70 percent are Democrats, according to Ballotpedia.

The group's resolutions have no legislative power, but are indicators of the top items on the agendas of the nation's cities.

Throughout their climate-related resolutions, the mayors sought to make the case for national leaders to elevate the cities' concerns, too.

"City/metro economies are home to 91 percent of Gross Domestic Product and wage income, and 88 percent of the nation's jobs," said the resolution calling for a comprehensive national climate policy. "Cities are facing tremendous financial losses in the billions of dollars due to the increased intensity of storms, flooding, drought, wildfires and coastal flooding, linked to rising global temperatures."

In their Green New Deal resolution, the group commended Mayors Eric Garcetti of Los Angeles and Svante Myrick of Ithaca, N.Y., for launching Green New Deal-style programs locally, and called upon state and local governments "to support these efforts on a national scale."

Support for Carbon Pricing

In the carbon pricing resolution, the mayors said such a measure "would encourage and empower households and businesses to invest in energy efficiency, conservation and domestic carbon-free energy sources," the resolution said. "Economists are in general agreement that market-based mechanisms such as carbon pricing will create price signals that efficiently inform energy investment decisions."

The mayors did not endorse any particular carbon pricing proposal. But their vote against immunity from climate lawsuits for fossil fuel companies put the city leaders clearly on the record in opposition to a key policy trade-off included in an oil industry-backed carbon pricing plan, developed by former Republican Secretaries of State James Baker and George Shultz.

The advocacy group Citizens' Climate Lobby, which has been pushing for bipartisan carbon pricing legislation that does not include such a trade-off, said the Conference of Mayors' vote was important call to action.

"Mayors are on the front lines of climate change," said Andres Jimenez, CCL's senior director for government affairs. "They're dealing with the on-the-ground impacts every day, and they know people in their cities want action."

Biskupski, a progressive mayor in one of the most conservative states in the country, has sought to distinguish herself as a climate leader since taking office in 2016. That year, Salt Lake City became one of the first major U.S. cities to commit to 100 percent clean and renewable energy; this year, Biskupski moved up the target date to 2030. She also sponsored a resolution that the U.S. Conference of Mayors adopted in 2017 in favor of cities setting 100 percent clean energy goals. "Climate change is messing with my ski season," she told Outside magazine in 2017. Not only winter sports, but Salt Lake City's water supply is threatened by decreasing snow.