House Speaker Tina Kotek said a company was hired to find the boycotting House Republicans and hand them the subpoenas.

Editor's note: Video is from Feb. 25

SALEM, Ore. -- Stymied by a walkout by Republican lawmakers in the Oregon Legislature over a climate change bill, Democrats on Thursday said they will issue subpoenas to try to compel their return.

Oregon has become a front line in the battle over how to address global warming, with Democrats prioritizing a bill that would charge polluters for carbon credits, and the minority Republicans objecting, saying it would increase costs for Oregonians.

The Republicans walked out of the Senate on Monday before the bill come to to the floor for a vote. House GOP members joined the walkout on Tuesday.

“It's not about any particular bill any more,” said Rep. Paul Holvey, chair of the House rules committee. "This is about our democratic process. This is about our institution. It's about fundamental principles of democracy.”

His committee late Thursday voted to issue subpoenas ordering absent House Republicans to appear before the panel to “testify about your unexcused absences ... the need for members to fulfill their oaths of office and constitutional duties as legislators.”

House Speaker Tina Kotek, appearing at a news conference afterwards with Holvey, said a company was hired on Thursday to find the boycotting House Republicans and hand them the subpoenas.

Last year, Republicans in the state Senate disappeared twice, over a different version of the climate bill and over an education-funding tax.

Gov. Kate Brown, acting on the request of Senate President Peter Courtney, both Democrats, ordered the state police to find them and bring them back. Many GOP lawmakers fled across state lines, out of reach of the state police. Courtney has said this time he is not requesting police intervention.

Holvey told reporters he is relying on the private company to find the absent GOP House members.

“Process servers have their own methodologies, and I'm not familiar with them,” he said. "They do a professional job, and we just rely on that professionalism.”

But Republicans might just ignore the subpoenas, which order them to appear before the House rules committee on March 5. Or they might argue against it, stringing out the clock before the 35-day 2020 legislative session is constitutionally mandated to end on March 8.

“I will be really honest,” Kotek told reporters. "I am not optimistic that we will resolve this. And this conversation for the subpoenas, and whether or not they honor them, could go past the constitutional deadline.”