You just don't know when to quit, do you?
Using your OWN logic, I couldn't call a rapist a "rapist" just because he'd done ONE EVIL thing.
You could call him a rapist, but, as far as I can tell, you couldn't call him "evil", even though the "one evil thing" was very evil.
As I said in another thread, I think we are required to judge deeds but enjoined from judging people.