A new law is about to be introduced in the US to close a loophole allowing rapists to attack Native American women and get away with it.

At the moment, most non-Native Americans aren't punished for incidents on Indian reservations because they operate their own courts which don't have the legislation to deal with them. State and federal authorities are generally too far away or too stretched for resources to take on cases of sexual violence. 

One-third of Native American women are raped during their lifetime, while 86 per cent of reported rapes on reservations are committed by non-Native Americans.

"What's happened through US Federal law and policy is they created lands of impunity where this is like a playground for serial rapists, batterers, killers, whoever and our children aren't protected at all," said Lisa Brunner, executive director of Sacred Spirits First National Coalition, to Sky News.

Faith Roy and her sister are Native Americans and were abused by a non-Indian man as children.

She believes he took full advantage of the loophole.