Here is the opinion in Amador County v. Dept. of Interior.

An excerpt:

In 2005, Amador County, California brought suit against the Department of Interior challenging the Secretary’s approval of a gaming compact between the Buena Vista Rancheria of Me-Wuk Indians (the “Tribe”) and the State of California. After nearly six-and-a-half years of litigation, the Tribe sought to intervene for the limited purpose of moving to dismiss the amended complaint under Federal Rule of Civil Procedure 19. The district court denied the motion as untimely, and this appeal followed. Because we conclude that the district court did not abuse its discretion, we affirm.

Briefs and lower court materials here.