Marguerite O'Brien was a woman killed after she was struck by a vehicle in 1985. She was identified in 2015 by DNA.
On August 3, 1985, a woman was killed when she attempted to cross a highway in Fontana, San Bernardino County, California. The female was between twenty-five and thirty-five when she died and was possibly native to the eastern part of the country. She was five feet eight inches tall and 150 pounds; she wore a red top, blue pants and boots. She also wore distinct earrings in the shape of insects and carried a purse with various colors that contained several phone numbers and addresses. Her hair was light brown; her eyes were either blue or hazel. She had some sort of surgery that removed one of her ovaries and her uterus, which was consistent with a scar on her abdomen. Another scar was also located on her back.