will I get into trouble for taking my kids off an Indian reservation even though I have a signed piece of paper from the father? I'm white

I'm a white lady getting a divorce from a Native American we live down the duck valley Indian reservation in Nevada I would like to know my rights on the reservation my husband is a police officer and is using his authority against me and telling me I have no rights on this reservation I need help and I want full custody of my children I took them off the reservation with the signed piece of paper from my husband saying I'm allowed to take them to Arizona I would really like some answers and to know if some of my rights on that reservation thank you