California Sen. Kamala Harris took aim at the White House's handling of the FBI investigation into sexual misconduct allegations surrounding Supreme Court nominee Brett Kavanaugh during a passionate Senate floor speech.

"This should have been a search for the truth," she said. "They should have been allowed to do their full job. But instead the White House did not allow it. This was not a search for the truth. Instead, this was about politics and raw power to push through an unfit nominee."

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Harris said the probe should not have been a criminal investigation as to whether a crime had occurred, but instead an investigation into whether Kavanuagh is "fit" to sit on the Supreme Court.

"There's been a lot of conflation around here about the subject and the need for an investigation into Dr. Ford's allegations," she said. "Ours was not a search to determine whether a crime occurred, ours was not a search to determine whether we had enough facts to prove beyond a reasonable doubt that a crime had occurred. No ours was an investigation to figure out enough about what happened to determine if Brett Kavanaugh is fit to serve on the highest court on our land."

The senator raised her voice as she asked, "Is he fit to be a jurist in the place where we have said justice in our country occurs?... When it comes to Dr. Ford's allegations, we fell short. We fell short. We did not do her justice, we did not do the American people justice."

Harris then criticized the White Houses' handling of the FBI probe.

"When the White House directed the FBI to do its work, it appears the FBI was not permitted to look at all of the allegations," she said.

She then provided a list of individuals the FBI did not interview in its investigation, including Christine Blasey Ford's husband and several of Kavanaugh's classmates in high school and college.

As for Kavanaugh himself, Harris said he lacks impartiality, integrity and truthfulness.

"The minimum standard for a Supreme Court nominee should be someone who we are confident will demonstrate impartiality, integrity and truthfulness, but the nominee we are voting on has not demonstrated those qualities," she said. "Every American is entitled to the benefit of the doubt, but nobody is titled to a seat on the United States Supreme Court."

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On Friday afternoon, previously undecided senators Susan Collins of Maine and Joe Manchin of West Virginia announced that they will vote for Brett Kavanaugh's confirmation, meaning his seat on the Supreme Court is all but guaranteed.

Eric Ting is an SFGATE staff writer. Email him at eting@sfchronicle.com and follow him on Twitter

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