This article describes what I explained some months ago in this blog, which is concept of a group who fervently hopes that a criminal or highly immoral scandal making person is "not one of us."
Well, the Madoff financial scandal is a larger example of such a fear coming true than I could even imagine. Here is a thoughtful look at the blemish that the Jewish community feels.
http://www.nytimes.com/2008/12/24/us/24jews.html