Transcript for Warren faces new questions on Native American claims

Now to new trouble for senator Elizabeth Warren, just days before she's expected to formally kick off her presidential campaign. "The Washington post" is out with a new report revealing a document where Warren claims native American heritage in her own handwriting and whit Johnson is here with more. Good morning. Reporter: Good morning to you. Senator Warren's biggest obstacle appears to be her own words and this time it's in writing. Her claims of native American ancestry prompting another apology and hasn't formally launched her presidential campaign yet. Rules made in walling matter and that's why I'm in this fight. Reporter: This morning, 2020 presidential hopeful Elizabeth Warren is facing renewed backlash over her claims of native American ancestry. "The Washington post" obtaining her 1986 registration for the state bar of Texas in which she listed her race as American Indian. No one, not even the president of the United States will ever take it away from me. Reporter: Warren has been plagued by criticism of her various claims of native here tan throughout other career touted as an example of diversity in Harvard's faculty in the 1990s. Warren says Harvard made that claim without her knowledge but defended her choice to list herself as a minority in a national directory of law professors. These are my family's stories. My papaw had high cheekbones like all of the Indians do. Reporter: The controversy a favorite pressure point of president trump who has repeatedly called her pocahontas and challenged the north to prove her heritage. I will give you a million dollars to your favorite charity paid for by trump if you take the test and it shows you're an Indian. Reporter: In October 2018 Warren did take a DNA test releasing the results in a campaign video claiming vindication. What do the facts say? The facts suggest that you absolutely have a native American ancestor in your pedigree. Reporter: Drawing criticism from the cherokee nation. Last week after immediating with leadership Warren issued Ang apology and this morning a spokesperson saying as senator Warren has said, she is not a citizen of any tribe and only tribes determine tribal citizenship. She is sorry that she was not more mindful of this earlier in her career. Now, a lot of the criticism has been over whether she used those claims to advance her career. This now marks the earliest documentation of that claim, agaihe put it in writing while registering for a professional organization. That changes things. It does. Whit, thank you.

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