From the earliest days of the PEP meetings I raised this issue that even one example of teachers being punished for political reasons that have nothing to do with their teaching taints attempts to remove truly poor teachers. Joel Klein of course has done nothing but support the most awful principals from hell (PFHs) no matter what the evidence.
I think the first case we (Betsy Combier) raised was that of Dr. Bob Drake, a chemistry teacher at Bronx HS of Science who was fired by PFH Valerie Reidy because he objected to her using "Dr." before her title since she was not a phd. Of course Klein ignored the case. Drake by the way was hired by other systems in top performing schools in the suburbs since then at much higher salary than he was getting here.
Reidy meanwhile continued her vendettas - most notably within the math department where 20 teachers filed a complaint against her and she had a top level math teacher and chapter leader U-rated -twice. He has since transferred with UFT assistance - which looks like a good thing on the surface but also shows how the UFT allows its chapter leaders to be eaten - which undermines the union at its core.
By the way, I am convinced that part of the core curriculum at the Leadership Principal training academies is how to defang and destroy union reps or activists...
http://ednotesonline.blogspot.com/