By Jon Keller

BOSTON (CBS) – In 2012, when the story of Sen. Elizabeth Warren‘s lifelong claim of Native American ancestry first emerged, Warren – then embroiled in a tough race against Sen. Scott Brown – gave a round of one-on-one interviews. And as others did, I focused on what I thought was the only meaningful question raised by the story: did she ever use her lineage to gain an affirmative-action benefit?

“Absolutely not,” Warren said.

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And in the seven years since, no evidence has emerged to contradict her.

Yes, Warren identified herself as a “minority” in a 1986 Association of American Law Schools directory, and as the Washington Post reported this week, wrote in “American Indian” on a Texas Bar Association registration card after being admitted to practice. Harvard once cited her as Native American in a grant application.

But an exhaustive Boston Globe report last year found no proof of any effort by Warren to capitalize on her belief in family lore, concluding instead that “it is clear that Warren was viewed as a white woman by the hiring committees at every institution that employed her.”

Still, the narrative developed by her political enemies seven years ago continues to be aggressively promoted, regardless of the facts. “Warren pretended to be a minority to climb the Ivy League ladder — a lie that will continue to haunt her presidential ambitions,” Mike Reed of the Republican National Committee told CNN.

The persistence of this lie is in part due to Warren’s defensive, at-times incompetent, handling of it. Page one of the political candidate’s handbook is to do thorough opposition research on yourself and be prepared to reveal anything remotely negative on your own terms rather than leave it to your adversaries to do so in a torturous slow-drip. The fact that details continue to come out all these years later speaks poorly of the senator’s political instincts and staff work.

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But the sight of reporters and pundits suggesting that Warren must now terminate her nascent campaign over this is puzzling.

Sen. Elizabeth Warren talks to reporters, Feb. 6, 2019. (Image credit: CBS News)

Since when was telling the truth – however haltingly – cause for aborting a serious candidacy?

Has Warren been caught cheating on her spouse, plagiarizing another candidate’s speech, misusing campaign funds, trying to cover up a crime, or committing any one of the multitude of offenses that have brought candidates down in the past?

No.

Note what we’re not hearing or seeing – any evidence to disprove her claim of distant Native American heritage, or anything to undercut what she told me seven years ago.

There are plenty of reasons to doubt Elizabeth Warren’s ultimate viability as a presidential candidate; my own skepticism about the electorate’s desire to be led by a left-leaning Harvard Law professor is well-documented. And her entire record is fair game for criticism.

But this story is the smear that just won’t die.

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And I can’t recall a more effective political smear that was based on less evidence than this one.

Jon Keller