I just wanted to say that in regards to the pedofiles that I have semi-direct knowledge, one of them has been banned from aikido (that sounds strange doesn't it) and the other was legally prohibited from working with children. Neither has been a teacher of mine in the class sense.
Colleen, based on what I read, you are a fairly grounded individual. Many folks who walk through the doors of an Aikido dojo are people looking for answers and lack such grounding. When graced with a very charismatic and powerful individual this line starts getting very blurry, very quickly. If a sensei preys on the weak in spirit I'd think the ethics get pretty clear really quick.