I guess I assumed you wanted an answer based upon the very minimal information posted in the paper. For me, there was not enough information provided to say with any certianty whether I could make a life and death decision.
While you may see some comparison in knowing an activity is perfectly legal and risking that a police officer might indeed mistakenly arrest you for it and the life and death decision one must make to involve themselves in a life and death situation they have no knowledge of or involvement with prior to someone pounding on their hood are dynamically different decisions and thought processes.
Considering the events from the press and the standard response many people have to high stress situation described, I would liken it to "buck fever" and say that many people whom would think they would jump out and give the guy a 230 grain lead injection would far more likely be victim number 1, she would be number 2 and he would still commit suicide.
I have no problem saying that I am not going to jump into a situation I do not know enough about to determine if I could make that life and death call. I am not willing to pretend that things should be different just because I know the outcome. Like I said the first time, I am sitting in my car, windows up, ac on, tunes playing and bam someone starts pounding on my hood, I may well have been killed as I would most likely have addressed her asking her WTF she was doing and he would have shot me in the back.
Sometimes you just have to not like the answers to the questions I guess.