David D. Haddock (Northwestern) has published To Tax Tribes or Not to Tax Tribes? That Is the Question, 12 Lewis & Clark L. Rev. 971 (2008).  Here is the abstract:

As a first approximation, a tax on a buyer has an impact that is identical to an alternative tax of equivalent size that is imposed on the seller. Students in an elementary microeconomics class quickly learn that fact, but Montana v. Blackfeet Tribe and Cotton Petroleum v. New Mexico imply that few justices or judges sitting on our courts have attained a similar level of economic sophistication. In view of the canons of construction of Indian law, and the understandings of the tribes when concluding treaties with the United States, Blackfeet Tribe quite properly repulsed Montana’s attempt to tax tribal royalties from on-reservation extraction of minerals. In contrast, Cotton Petroleum permitted New Mexico to tax the companies that held mineral extraction leases on tribal land. The two holdings, handed down less than five years apart, are mutually inconsistent. The inconsistency provides an incentive for tribal governments to enter lines of business for which private ventures would have been more efficient. By so doing, the tribes will be able to withhold some tax revenues from states, though at the cost of less efficient on-reservation enterprise and a consequent reduction in employment.