SIOUX CITY, Iowa — Senator Elizabeth Warren of Massachusetts is set to appear at a candidate forum on Monday dedicated to issues affecting Native Americans, an event that will likely draw attention to her past claims of Native American ancestry.
Ms. Warren, in keeping with her reputation as the presidential candidate with an enormous collection of detailed plans, has made a concerted effort to develop a policy agenda that would help Native Americans.
But her appearance at the forum, in Sioux City, will likely be closely watched because of her history of stumbles over the subject, an issue that is certain to be used against her if she is the Democratic nominee. Ms. Warren faced criticism from some Native Americans last year after she released the results of a DNA test that provided evidence she had a Native American ancestor. After entering the presidential race, she apologized for the DNA test and for identifying herself as Native American during her career as a law professor.
“Goodness knows, like anyone who’s being honest, I know I’ve made mistakes and I have regrets and I’ve apologized for them,” Ms. Warren said last week during a question-and-answer session with the Working Families Party. “But I try every day to be a good partner, and to be a good partner means to think about investment in tribal areas. It means about making sure that Indian Country is represented at the table when we’re talking about how to put policies together.”
On Friday, Ms. Warren rolled out a set of proposals intended to help Native Americans, covering topics like tribal sovereignty and missing indigenous women. She also released a wide-ranging legislative proposal with Representative Deb Haaland, Democrat of New Mexico, one of the first Native American women to serve in Congress. The proposal covers areas like criminal justice, health care and economic development.
In addition, some of the policy plans Ms. Warren released earlier in her campaign would provide funding earmarked for Native American communities to address issues like housing and the opioid crisis. She has also worked on Native American matters in the Senate, sponsoring legislation about suicide prevention and child abuse in Native communities.
The two-day forum, named in honor of Frank LaMere, a Native American activist who died in June, is being hosted by Four Directions, a Native American voting rights group, and the Native Organizers Alliance. Other candidates scheduled to attend include Senators Bernie Sanders of Vermont and Amy Klobuchar of Minnesota, as well as Julián Castro, the former housing secretary, who last month released his own plan to support indigenous communities.
OJ and Barb Semans, the co-executive directors of Four Directions, decided that Ms. Warren would not be asked about her ancestry during her appearance, Mr. Semans said in an interview. He said the Warren campaign made no requests about what she would or would not be asked.
Mr. Semans, a member of the Rosebud Sioux tribe, faulted President Trump for mocking Ms. Warren by calling her “Pocahontas.” He said he had no problem with how Ms. Warren had referred to her ancestry, and that it was more important to spend time on issues that could help the lives of Native Americans, “not whether or not her DNA test was done properly or improperly.”
“How many times do you have to argue something that’s already done?” he asked. “That issue has been dealt with, it’s been taken care of, and we move on. But what hasn’t been dealt with and taken care of is President Trump’s continued use of it in a derogatory way.”
It remains to be seen how much the ancestry issue will linger over Ms. Warren as the campaign goes on. At a rally in New Hampshire last week, Mr. Trump repeated the “Pocahontas” slur and promised there would be more to come.
“I did the Pocahontas thing,” he said. “I hit her really hard, and it looked like she was down and out, but that was too long ago. I should have waited. But don’t worry, we will revive it.”
No amount of outreach or contrition from Ms. Warren will make the issue go away entirely among some Native Americans, said Mark Trahant, the editor of Indian Country Today, who is moderating the forum.
“There is a significant group, mostly on Twitter but significant nonetheless, who will never take any apology from her,” he said. “They see it as a felony.”
Ms. Haaland, who endorsed Ms. Warren last month, takes a different view than those critics.
“I think she’s been able to move past it, quite frankly,” she said. “Her heart is in the right place. She cares deeply about Indian Country.”