From the Sentencing Project (http://www.sentencingproject.org):
The number of American Indians and Alaska Natives (AIAN) held in local jails nearly doubled from between 1999 and 2014, according to a Bureau of Justice Statistics analysis covered by The Crime Report. During this period, the AIAN population in jails outside of Indian country increased by an average of 4.3% per year, compared to an increase of 1.4% per year for all other races combined.
While the AIAN population in jails was half as likely as the non-AIAN population to be held for a drug offense (12% versus 24%), they were over twice as likely to be held for a DWI/DUI of alcohol or drugs (14% versus 6%). In total over 34,000 American Indian and Alaska Natives were held in jails within and outside of Indian country and in state and federal prisons in 2014.