Here is the opinion in Grigbsy v. LaHood.

An excerpt:

In the midst of his training, Grigsby became aware of his Native American heritage. He educated himself about his Sioux, Cherokee, and Apache roots and began to  share his background with his coworkers. Grigsby claims that this led to a  number of hostile comments from his coworkers, who began to call him “Chief,” “Running Planes Together,”  and “Metal Rain,”  among other insults. While  Grigsby did not  file  a  complaint regarding  these comments, he did request a  transfer to another facility, ostensibly to escape this  abuse.