SALEM — Oregon Gov. Kate Brown deployed the state police Thursday to try to round up Republican lawmakers who fled the Capitol to block a vote on a landmark economy-wide climate plan that would be the second of its kind in the nation.

Minority Republicans want the cap-and-trade proposal, which is aimed at dramatically lowering the state’s greenhouse gas emissions by 2050, to be sent to voters instead of being instituted by lawmakers — but negotiations with Democrats collapsed, leading to the walkout, Kate Gillem, a spokeswoman for Senate Republicans said Thursday.

Oregon State Police can force any senators they track down in Oregon into a patrol car to return them to the Capitol, although the agency said in a statement that it would use “polite communication” and patience to bring the rogue lawmakers back.

Sen. Bill Hansell, R-Athena, said Thursday evening that he had left the state and was somewhere “south of Oregon.” As far as he had heard, all of the other Republican senators were also outside of OSP’s jurisdiction.

“The governor had made it clear she was going to mobilize state police and we didn’t really know what that would mean,” he said. “Would they force us to come back? Encourage us to come back? How extensive would the search be?”

He said he had received a text message from OSP superintendent Travis Hampton asking where he was.

Under state law, the absentee senators will be fined $500 a day per person starting Friday if enough of them remain absent to prevent a vote. Democrats have an 18 to 12 majority in the chamber, but need 20 members present for a quorum.

“It’s time for the Senate Republicans to show up and do the job they were elected to do,” Brown, a Democrat, said at a news conference.

Republican senators appeared unfazed and ready to dig in.

“Send bachelors and come heavily armed,” Sen. Brian Boquist, a Republican from Dallas, said late Wednesday as the prospect of a walkout loomed. “I’m not going to be a political prisoner in the state of Oregon. It’s just that simple.”

Boquist, who is reportedly in Idaho, did not respond to emails after the Senate president publicly rebuked him for the remarks.

This is the second time in this legislative session that minority GOP lawmakers have used a walkout as a way to slow the process. Democrats have a rare supermajority in the House and Senate, meaning Republicans don’t have many ways to influence the debate.

Republicans walked out of the Senate last month to block a school funding tax package. The standoff lasted four days, until the governor struck a deal to table legislation on gun control and vaccine requirements.

Hansell said that the written deal also included language that there would be a “reset” on cap and trade. He said when Republicans felt the deal had been nullified, with no real changes on House Bill 2020, Sen. Cliff Bentz spent several “intense” hours negotiating a deal with Brown’s chief of staff Nik Blosser and Rep. Karin Power, D-Milwaukie.

One of the most important aspects to Hansell was taking out the bill’s emergency clause in order to give citizens time to put together a ballot referendum, but he said Bentz told him that was a “nonstarter” for Power and Blosser.

After Democratic leaders rejected the deal that was worked out shortly before 8 p.m., the Republican senators decided to go on strike.

“It’s a decision we didn’t take lightly, and we tried to avoid it,” Hansell said.

He said if the vote hadn’t been coming up so quickly they would have stayed to continue negotiating, and were still willing to negotiate. They were also willing to stay outside the state until after the session was constitutionally required to end, however, if Democrats wouldn’t budge.

The walkout tactic is rare, but it has been used throughout history. Abraham Lincoln once leapt out of a window in an attempt to deny a quorum when he was a lawmaker in Illinois.

In 2003, Texas Democrats fled to neighboring Oklahoma to deny a quorum, holing up in a Holiday Inn to block a GOP redistricting bill. The Democrats returned to Texas after the bill’s deadline passed, and it was effectively killed.

On Thursday, Oregon’s Senate president pleaded with Republicans to return.

“I beg and beseech my fellow legislators to come to the floor. I need you, the Legislature needs you, the people of Oregon need you to pass budgets to take care of our citizens,” Senate President Peter Courtney said on the Senate floor.

The walkout brings all Senate business to a halt with just over a week left in the legislative session. Senators still need to vote on the budget.

But the cap-and-trade legislation remains a sticking point.

Under the proposed bill, Oregon would put an overall limit on greenhouse gas emissions and auction off pollution “allowances” for each ton of carbon industries plan to emit. The legislation would lower that cap over time to encourage businesses to move away from fossil fuels: The state would reduce emissions to 45% below 1990 levels by 2035, and 80% below 1990 levels by 2050.

Those opposed to the cap-and-trade plan say it would exacerbate a growing divide between the liberal, urban parts of the state and the rural areas. The plan would increase the cost of fuel, damaging small business, truckers and the logging industry, they say.

“Protesting cap and trade by walking out today represents our constituency and exactly how we should be doing our job,” said Senate Republican Leader Herman Baertschiger, Jr., of Grants Pass.

A small group of loggers gathered to protest outside the Capitol on Thursday.

Bridger Hasbrouck, a 32-year-old self-employed logger from Dallas, said the bill if passed would be “devastating” to his business because he uses diesel fuel to power all his logging equipment.

“There’s a whole lot involved but the biggest thing that’s very crippling is the fact that these bills would impose regulations that would take trucks off the road that people are using to earn their living,” he said.

Democrats say the measure is an efficient way to lower emissions while investing in low-income and rural communities’ ability to adapt to climate change. It has the support of environmental groups, farmworkers and some trade unions.

The proposal also contains a $10 million investment to protect workers adversely affected by climate change policy.

“‘Rural’ here is not one voice,” said Mimi Casteel, a farmer in rural Hopewell, Oregon. “This is not just about gas prices — this is about the future of humanity.”

California has had for a decade an economy-wide, cap-and-trade policy like the one Oregon is considering. Nine northeastern states have more limited cap-and-trade programs that target only the power sector.

East Oregonian reporter Jade McDowell contributed to this story.

“The governor had made it clear she was going to mobilize state police and we didn’t really know what that would mean. Would they force us to come back? Encourage us to come back? How extensive would the search be?”

 — Sen. Bill Hansell, R-Athena