To find this out, you have to look in a couple of different chapters.

In Chapter 1, Nick remembers that he has heard some sort of a story that has to do with something that Jordan did at a golf tournament.

But then later on in Chapter 3, we actually find out what the story is.  The story is that she was accused of moving her ball to a better "lie" (golf term for where your ball is, what's around it, stuff like that).  This is a big no-no in golf -- serious cheating -- and that's what Jordan was accused of.