Among other things, Tennessee railroad worker Thurston Hensley sought monetary damages for a fear of developing cancer in the future.

CSX argued that the instructions given to the jury were too friendly to Thurston. The company wanted jurors to be instructed that Thurston needed to demonstrate that his fear of cancer was genuine and serious.

The Supreme Court, in an unsigned opinion, said it was a "clear error" for the trial judge not to give the jury instructions CSX requested.

The high court sent the case back for new court proceedings.