I think they should. However, the problem isn't about race at all. The tribe is attempting to play that card, and I hope they are successful.
The problem is an antiquated system of apportioning water rights. Presently California owns Colorado River water as far inland as Colorado. Even the water that the Navajo take from the Animas river and the San Juan River are subject to California claims as they are part of the Colorado watershed.
If the Navajo are successful with this case, it will affect most of the southwest. Last year the federal government decreed that all states and entities with an interest in the Colorado River Basin water work out a plan to modernize the way the water is apportioned. The only entity to refuse this decree is the state of California.
That brought about the Navajo Nation bringing this suit. Because of their status as a sovereign nation, they get their case to the supreme court right away. It should be noted that all the states EXCEPT California, involved in the Colorado River compact, (Arizona, Nevada, Utah, new Mexico and Colorado) support the Navajo Nation in various ways in this endeavor to force California to the bargaining table.
It isn't about race, but race is being used to force this issue.