"I have always had the deepest respect for the remarkable institution that is the Oregon Legislature; and for the office of the Governor," Kitzhaber said in a recorded message. "And I cannot in good conscience continue to be the element that undermines it. I have always tried to do the right thing and now the right thing to do is to step aside."
The resignation will take effect next Wednesday, at which point Democratic Secretary of State Kate Brown will take over as governor. Human Rights Campaign, the nation's largest LGBT rights organization, trumpeted her promotion Friday as the ascension of the nation's first openly bisexual governor.
Kitzhaber's decision to step down came as little surprise, as he had faced mounting calls to resign this week over reports indicating his finacee, Clivia Lynne Hayes, advised the governor and state employees on energy policy while getting paid by a group advocating on the issue.
The state Attorney General opened a criminal investigation into the case on Monday, and on Thursday night, state troopers gathered outside his Portland-area home, leaving after a fruitless hours-long stakeout with no sighting of the governor.
The resignation came as the Oregon Department of Administrative Services served criminal subpoenas on Kitzhaber and Hayes. The subpoenas seek emails, letters and financial information concerning a wide range of activities, including state business.
Kitzhaber said Friday, however, "I am confident that I have not broken any laws nor taken any actions that were dishonest or dishonorable in their intent or outcome," and asserted that the AG and ethics investigation into his fiancee's work would ultimately exonerate him in the eyes of Oregonians.
But he also acknowledged that the questions dogging his administration over his fiancee's policy work, "and the escalating media frenzy that has stemmed from this, has clearly reached the point of no return."
And, voice wavering, he expressed a love for Oregon, "its people, its rivers, its mountains and its landscapes, with every fiber of my being."
It was a dramatic end for a governor that made Oregon history just three months ago by winning an unprecedented fourth term in office. But it was one, Oregon political observers say, that was not entirely unexpected.
The latest scandal wasn't the first time Kitzhaber's fiancee had caused the governor trouble. Questions surrounding her role as an adviser to the governor, while still doing consulting work on the side, dogged them both during his 2010 reelection campaign.
Many in the state suggested the governor may have let his relationship cloud his judgment.
"Love is blind — that's all I'm going to say," Oregon Democratic Rep. Kurt Schrader told CNN in Washington on Friday.
The reports that prompted Kitzhaber's resignation emerged before he was reelected, but Kitzhaber was largely able to ignore them, riding Oregon's heavily Democratic electorate and a flawed Republican challenger to victory last fall. But details surrounding the scandal continued to trickle out over the past few months, and the situation came to a head last week with the state's largest paper, The Oregonian, calling on him to resign.
On Monday, the Oregon attorney general opened up an investigation into the situation. And Kitzhaber stoked the controversy this week by reportedly deciding to resign by Tuesday, and in a move his secretary of state called "bizarre and unprecedented," changing his mind by Wednesday afternoon.
Brown outlined her experience during the saga in a statement, saying she received a call from Kitzhaber late Tuesday afternoon asking her to return to Oregon from Washington "as soon as possible to speak with him in person and alone."
When she returned, late Wednesday afternoon, Brown said things had changed.
"I was escorted directly into a meeting with the governor. It was a brief meeting. He asked me why I came back early from Washington, D.C., which I found strange," she recounted in her release. "I asked him what he wanted to talk about. The governor told me he was not resigning, after which he began a discussion about transition."
Brown added: "This is clearly a bizarre and unprecedented situation."
She said she told the governor she and her staff would be ready if he resigns. And the call for him to do just that grew louder into Thursday, with state Treasurer Ted Wheeler becoming the first Oregon elected official to publicly call for Kitzhaber to step down.
In a statement, Wheeler said the governor "has accomplished many great things during his long career, and history will be kinder to him than current events suggest."
"Unfortunately, the current situation has become untenable, and I cannot imagine any scenario by which things improve. Oregon deserves a Governor who is fully focused on the duties of state," Wheeler said.
On Friday, the overarching consensus in Oregon was that Kitzhaber had done the right thing, and that his resignation would, as Sen. Ron Wyden put it in a statement, let the state "refocus" on its goals. .
"Oregonians have a right to expect the highest ethical standards from their government, and today's announcement by Governor Kitzhaber acknowledges that reality," the Democratic senator said. "In the days ahead, we will refocus with our new Governor Kate Brown on the goal all Oregonians share - making the best state in America even better."