this is America, so legally, whoever has the most expensive lawyer is in the right
morally, the person who opens the door is being careless
practically, the cyclist who gets doored just had some bad luck
I used to live near a university for 10 years. I've been doored more times than I can remember. Even if you are on the lookout, some guy looking for a bookbag in his back seat will pop up and throw the door of his Jetta open right when you get there.
you want to ride without being doored?
you gotta move out of town