Eliza says

"he appeared to be compassionate and gentle (which perhaps he was.) "

Human beings are very complex and are neither completely evil or good. Even the the most saintly and altruistic individuals may have several character imperfections and, possibly, hidden secrets.

Of course, certain forms of behaviour such as that in which Harris, Savile, and others have indulged are totally unacceptable and can't be condoned. All the "good points" are inevitably cancelled out.