The greenhouse gas cap-and-trade bill that Oregon Republicans fled the Capitol in order to kill is on track to die Thursday unless the missing lawmakers return.

Republicans in the state Senate have shut down business for more than a week, denying Democrats the two-thirds quorum they need to vote on the climate change bill and other legislation.

Although the 35-day legislative session does not end until midnight Sunday, Senate Bill 1530 still needs to clear several procedural steps and a floor vote in each chamber in order to pass.

Lawmakers can speed up bill passage by suspending procedural rules, as they did after Senate Republicans returned from their second 2019 walkout last June. But Democrats said Wednesday they would only do so for all bills still in play — not just the budgets and other legislation Republicans might want to return and pass.

As a result, Thursday also likely spells the end of the line “really for everything at this point,” Sen. Michael Dembrow, D-Portland and a longtime proponent of cap-and-trade, said on Wednesday.

Sen. Mark Hass, D-Beaverton, concurred. “The Democrats are pretty strong about if there’s a rules suspension it’s universal,” Hass said on Wednesday.

A spokeswoman for Senate Republicans could not immediately be reached for comment late Wednesday afternoon.

House Republicans have also been boycotting the Capitol for more than a week, even though it was unclear how quickly cap-and-trade would move to the lower chamber if enough Senate Republicans returned to allow it to pass. Senate President Peter Courtney D-Salem, has said his caucus has enough votes to pass Senate Bill 1530.

One Republican in each chamber has continued to attend all floor sessions, Rep. Cheri Helt and Sen. Tim Knopp, both of Bend.

Gov. Kate Brown, a Democrat, has said she would consider calling lawmakers back to Salem for a special session if the regular short session ends with most Republicans still absent. It remains unclear when that would be or what bills Brown might ask them to consider.

Lawmakers typically adjourn by passing a resolution ending the session “sine die,” Latin for “without day.”

Without at least two Republicans necessary to reach a quorum in each chamber, legislators face the highly unusual prospect that this year’s session will simply expire on its own.

“Obviously, we can’t pass the sine resolution without a quorum,” Dembrow said.

— Hillary Borrud | hborrud@oregonian.com | 503-294-4034 | @hborrud

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