Donald Trump is still questioning Kamala Harris’ racial identity. At the ABC News presidential debate, ABC’s David Muir asked Trump to explain why he questioned Harris’ mixed-race identity in July.

“I didn’t know she was Black until a number of years ago, when she happened to turn Black, and now she wants to be known as Black,” he said then about Harris at the National Association of Black Journalists’ annual convention. “So, I don’t know, is she Indian or is she Black?”

“Why do you think it’s appropriate to weigh in on the racial identity of your opponent?” Muir asked the former president on Wednesday.

“I don’t and I don’t care. I don’t care what she is. I don’t care,” Trump answered. “You make a big deal out of something...I couldn’t care less. Whatever she wants to be is OK with me.”

“But those were your words,” Muir replied, urging him to clarify.

“I don’t know. I don’t know. All I can say is I read where she was not Black ...and then I read that she was Black and that’s OK, either one was OK with me,” Trump finally said, doubling down on the premise that Harris is not Black. “That’s up to her.”

Harris responded by bringing up Trump’s long history of racism. “I think it’s a tragedy that we have someone who wants to be president who has consistently, over the course of his career, attempted to use race to divide the American people,” she said.

Harris then reminded viewers that Trump was once sued for not renting to Black people and spread the racist birther lie about former President Barack Obama. And that he took out a full-page ad in the New York Daily News calling for the execution of five Black and Latino boys who were falsely accused of sexual assault in 1989.

“I think the American people want better than that,” Harris said.