These things never end well...

Not to be judgmental, but when will teachers learn not to boff their students? Perhaps I'm missing something, but I haven't heard about any situation like this that has ended well. The latest involves the trial of Eric McLean, who is charged with the murder of his wife's 18-yr-old student-lover: http://www.cnn.com/2008/CRIME/09/05/teacher.sex.slaying.ap/index.html?iref=mpstoryview