Follow the links, meself. That is the case. Native authority deals with Native offenders. They have no legal standing with outsiders and for a variety of reasons neither the federal nor state governments choose to go after the offenders even when they know who and where they are.

After NPR started looking into a rape/murder case which had been ignored by authorities, it was reopened. A young woman was beaten and raped. While locked in a bathroom she took some medications hoping that someone would call an ambulance if she appeared seriously ill. An ambulance was called. In the hospital she identified her attackers and then died from her injuries. No investigation was made.