When it comes to collecting back taxes, nothing is too sacred for the Internal Revenue Service. The IRS last week auctioned off more than 7,000 acres of land in Central South Dakota belonging to the Crow Creek Sioux Tribe, which owed $3.1 million in unpaid taxes and penalties to the federal government. The land, located within the tribe’s ancestral territory, included a swath being readied for a potential wind farm project that tribal leaders were negotiating. Although valued at $4.6 million, the 7,100 acres was sold for less than $2.6 million to an undisclosed buyer. Tribal officials have filed suit in federal court challenging the sale. In the lawsuit they claim that in 2003 the Bureau of Indian Affairs erroneously advised them that the tribe did not have to pay federal employment taxes because the Sioux are a sovereign nation. The trial is not expected to begin until late March.