A woman who claimed to be “transracial” and born in the wrong coloured skin has created a new debate on whether one can cosmetically switch to another race.

US civil-rights activist Rachel Dolezal is facing questions over whether she lied about her racial identity, with her family saying she portrays herself as black despite being caucasian.

Ms Dolezal’s estranged mother, Ruthanne, said the family is Czech, Swedish and German, with some Native American roots.

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But Rachel Dolezal, who heads a local branch of the National Association for the Advancement of Colored People (NAACP) in northwestern United States, would not answer questions about her background in an interview with a local newspaper.

“That question is not as easy as it seems,” she told The Spokesman-Review on Thursday. “There’s a lot of complexities. And I don’t know that everyone would understand that.”

Ms Dolezal is president of a local branch of the civil-rights organisation, an adjunct professor in the Africana Studies Program at Eastern Washington University and chairwoman of the local police overnight board.

Basically blackface

Her adopted brother Ezra has been quoted saying Rachel’s actions amount to “blackface”, a derogatory performance by white people with dark make-up on their faces, to impersonate African people.

“She puts dark make-up on her face and says she black,” Ezra Dolezal, 22, told Buzzfeed News. “It’s basically blackface.”

He said she pleaded with him not to “blow her cover” before she moved to Spokane, Washington and adopted the new racial identity.

“She just told me, ‘Over here, I’m going to be considered black, and I have a black father. Don’t blow my cover’,” he said.

“She wanted to make a new life for herself but she took it to the ultimate extreme,” Mr Dolezal said. “Not only did she move out to Spokane, but she created a whole new identity for herself.”

Did Rachel break the law?

Spokane authorities said an inquiry is under way into whether Dolezal violated city polices when she stated her racial identity.

Ruthanne Dolezal said that she and her daughter have not been in touch for years but that Rachel Dolezal began to portray herself as African-American eight or nine years ago after the family adopted four black children.

“It’s very sad that Rachel has not just been herself,” the mother told the newspaper by phone from her home in Montana.

“Her effectiveness in the causes of the African-American community would have been so much more viable and she would have been more effective if she had just been honest with everybody.”

The NAACP has released a statement saying it respects Ms Dolezal’s privacy in the matter.

“One’s racial identity is not a qualifying criteria or disqualifying standard for NAACP leadership,” the group said. “In every corner of this country, the NAACP remains committed to securing political, educational, and economic justice for all people.”

– with AAP