Early Tuesday morning, in Oregon, Shilpa Joshi, the coalition director of Renew Oregon, a clean-energy advocacy organization, rented a minivan from a lot on the outskirts of Portland, picked up a group of high-school students, and headed for the state capitol building, in Salem, where they’d be staging a protest. She was anxious and deeply concerned. “This might be a really sad day for us,” she said, en route. A major climate-change bill, which she had worked on for the last several years, was on the verge of passing the state legislature, which, since last year’s midterm elections, has been controlled by a supermajority of Democrats. Governor Kate Brown, a Democrat, had campaigned on its policies, and planned to sign it. On climate policy, Brown had said, “Oregon can be the log that breaks the jam nationally.” Then, last week, eleven Republican state senators walked out of the statehouse, fled the capitol, and apparently hid out of state, in order to deny the rest of the Senate the necessary twenty-person quorum required to move the bill to a vote. Representatives of fringe right-wing militia groups said that they would protect the state senators “at any cost,” and that protesters supporting the bill at the capitol should be warned of their presence. “Our bill might die,” Joshi said. “What these senators are doing is anarchistic. It’s scary. There are no rules anymore.”

In Salem, Joshi and her high-school group, along with other young activists, staged a sit-in outside the office of the Senate president, the Democrat Peter Courtney. Joshi and other organizers had heard that Courtney was prepared to trade away the bill in order to bring the Republicans back to the statehouse. “For him to just undercut us that way was a real blow,” she said. “We fought for so long and created a really strong program with pretty broad support across the state.” The oldest farm workers’ union in the state, for instance, joined Renew Oregon’s steering committee, in part because of “the immense pressures that climate impacts put on their workers,” Joshi said. (The average life expectancy of an Oregon farmworker is forty-nine years.) After lengthy negotiations, public meetings, and citizens’ comments, the bill also gained backing from all nine of the state’s federally recognized Native American tribes, the state’s electric utilities, who were, at first, opposed, and corporations in the state including Nike and Uber. As of eleven days ago, widespread consensus existed that the bill would pass. “We had the votes last week,” the state senator Michael Dembrow, one of the bill’s co-authors, told me on Tuesday.

The main goal of the bill is to set up a cap-and-trade program that will dramatically and rapidly lower greenhouse-gas emissions across the entire economy, reaching an eighty-per-cent reduction below 1990 levels by 2050. The state government would establish a certain amount of permits, called allowances, which companies could buy for every ton of carbon dioxide (or its equivalent) that they emitted; over time, the total number of allowances would decrease, forcing companies to adopt technology that would steadily reduce over-all pollution levels. Companies would also be allowed to buy and sell allowances in regular auctions. Money raised from the program would be invested in further emissions-reduction and climate-mitigation measures across the state, focussing on low-income, rural, and tribal communities that are most vulnerable and least able to prepare for the increasingly severe weather that will hit as temperatures continue to rise. The bill also sets aside ten million dollars every two years to protect workers in transportation and manufacturing, who could face layoffs. (Provisions included unemployment benefits and transition programs, such as training for clean-energy jobs, which will be required, also under the law, to feature competitive wages and benefits.)

Criticism of the bill initially came from both sides of the political aisle. Some environmental-justice advocates on the left were concerned that the program would allow companies to fulfill up to eight per cent of their compliance obligations by purchasing carbon-offset credits from forestry projects, which must show that, through their management practices, they are sequestering greater amounts of CO 2 from the atmosphere than whatever was there before. Offset programs, critics say, let power plants and industry increase pollution in certain communities while buying offsets elsewhere, and have a troubled compliance record.

The much more vocal criticism, on the right, came from manufacturing companies, truckers, small-business owners, and farm owners, who said that the program would raise fuel prices and energy bills. In response to their concerns, Dembrow and Representative Karin Power made compromises; the bill would subsidize ninety-five per cent of the allowances for companies that are particularly trade-exposed (paper mills, aluminum, concrete, and food processing), which are the most vulnerable to energy-cost increases. It’s true that a cap-and-trade bill would increase energy costs slightly. “That’s how they send signals in the market, and that’s how the market works,” Leah Stokes, an assistant professor in the department of political science at the University of California, Santa Barbara, and the author of a forthcoming book on the battle over climate policy in American states, told me. That’s also, she said, “why cap-and-trade and carbon taxes have struggled to get passed around the world.” She pointed out that, in this country, decades of wage stagnation and growing inequality have led to a situation where people—like those in rural areas in Oregon—do not have enough money to pay their monthly bills. “That’s why you have to think about climate policy in more systemic ways, protect people, bring them along in transition.” The Oregon bill, she said, did that, by taking money from the cap and investing it in the transition.

Nevertheless, last Thursday, the Senate’s Republican leader, Herman Baertschiger, announced that his caucus would take action to prevent the cap-and-trade bill’s passage. Governor Brown said she would respond by calling for a special legislative session, and, if necessary, was willing to ask for state troopers to help return the missing lawmakers to Salem. Afterward, the Republican senator Brian Boquist said in a local television-news interview that he had spoken to the Oregon State Police’s superintendent and told him, “Send bachelors and come heavily armed. I’m not going to be a political prisoner in the state of Oregon. It’s just that simple.”

The next day, June 20th, when the cap-and-trade bill was up for a vote, the Republican senators did not arrive for the 11 A.M. legislative session. Courtney asked the sergeant-at-arms to search for the missing members. They were nowhere to be found. He then asked Governor Brown to dispatch state troopers to find the senators and bring them back to the capitol to do their job. “It is absolutely unacceptable that the Senate Republicans would turn their back on their constituents who they are honor-bound to represent here in this building,” Brown said. “They need to return and do the jobs they were elected to do.” Boquist’s wife, Peggy, told CNN that the eleven senators were together, hiding in Idaho. Representative Tim Knopp, a Republican, said that he had been hiding in three different states over three days. Meanwhile, Carol Williams, a resident of Silverton, Oregon, created a GoFundMe page called “Encourage the Walking Senators.” (As of Thursday, eight hundred and twenty-one people had raised $43,307 in seven days.)