Blood quantum laws

Blood quantum laws are rules that were made in the past to decide who is allowed to be a member of a Native American tribe and who isn't. To be a member of a tribe, a person needs to have a certain amount of "Native blood" or Native ancestry. This amount is the "blood quantum" and varies from tribe to tribe. The blood quantum requirement is usually a certain percentage, like 25%, which means that a person needs to have at least 25% of their ancestors be Native American to be a member of the tribe.