PASS (verb) \`pas\ to identify oneself or be identified as something one is not.

"She thought it to her interest, on going to Washington, to assume the role of a white woman, and by her dress and conduct as such I am not aware that her identity as Harriet Hemings of Monticello has ever been discovered." – Madison Hemings, 1873, on his sister Harriet who was allowed to leave Monticello in 1822.

If you were a freed slave with light skin, would you try to pass as a white person in order to increase opportunities for yourself?