Republican gubernatorial candidate Knute Buehler arrives for his third and final debate with Gov. Kate Brown. Dirk VanderHart / OPB

Knute Buehler turned heads last week, when he

THANKS TO OUR SPONSOR: Become a Sponsor

announced he supports

Oregon parents' right not to have their children vaccinated without a medical reason.

In his third and final debate with Gov. Kate Brown, the Bend surgeon and Republican candidate for governor said he believes in the benefits of vaccines, with a caveat.

“I also think that parents should have the right to opt out — to opt out for personal beliefs, religious beliefs or even if they have strong alternative medical beliefs,” the candidate said. “I think that gives people option and choice.”

The stance has since earned Buehler criticism from his peers. On Monday, three Oregon physicians’ groups released a statement condemning Buehler’s position on the matter, saying Oregon’s low vaccination rate puts kids at risk of preventable disease. The organizations called on Buehler to change his stance.

Related: Knute Buehler Says He's A Different Kind Of Republican

THANKS TO OUR SPONSOR: Become a Sponsor

As it turns out, he already has.

As a freshman legislator in 2015, Buehler voiced support for tightening Oregon vaccination laws. He testified in favor of a bill that would have eliminated nonmedical exemptions in state law, thereby forcing parents to vaccinate their children despite philosophical or religious objections.

"This bill is so important in removing nonmedical exemptions for vaccinations and ensuring that kids are really safe from these preventable diseases," Buehler testified before the Senate Committee on Health Care in February 2015. "I'm all about freedom — that's one of my core beliefs — until it starts to do harm to others. And this is really the key issue with regard to vaccinations."

The bill Buehler stumped for that day, Senate Bill 442, didn't wind up going anywhere. Its chief sponsor, Democratic state Sen. Elizabeth Steiner Hayward, says she doesn't understand Buehler's change of heart.

“I was just stunned when he said that during the debate,” Steiner Hayward, a physician herself, told OPB. “He appears to me to be compromising his principles.”

An inquiry to Buehler’s campaign Tuesday about his change of heart wasn’t immediately answered.

The Daily Beast, which first pointed out the candidate's switch in position, notes that one of Buehler's campaign aides helped fight the 2015 vaccination bill. Rebecca Tweed, a senior official on the Buehler campaign, was affiliated with the opposition group Oregonians for Medical Freedom at the time the bill was being considered.

Oregon has one of the lowest vaccination rates in the country, with more than 7 percent of parents of kindergarten-age children opting out for nonmedical reasons.

Oregon law allows parents to make that decision once they view online informational material or consult a doctor.

Doctors’ groups believe the law leaves Oregon vulnerable to diseases like whooping cough or the measles, which are preventable when enough of the population is vaccinated.

“There are diseases that we have previously caused to become very rare in the United States which are now making a resurgence because of lack of widespread vaccination in the population,” said Dr. Robyn Liu, a family doctor and president of the Oregon Academy of Family Physicians, one of three groups that called on Buehler to reverse his position. “We all felt very strongly that, particularly in this time, it was important to speak out about the importance of strong vaccination policy for the health of vulnerable people in Oregon.”