The report notes high rates of poverty, disease, and alcoholism, but doesn't mention drug abuse. It also notes that indigenous peoples are disproportionately incarcerated, but it doesn't say whether drug-related convictions play a role in this. In listing federal programs that affect indigenous peoples, the report notes a few law enforcement programs aimed at reducing crime, including one funded by the Office of National Drug Control Policy. It does not note what effect these drug enforcement programs have on indigenous communities.
Citation: James Anaya, 'Report of the Special Rapporteur on the rights of indigenous peoples: The situation of indigenous peoples in the United States of America' (2012) A/HRC/21/47/Add.1