I found an article also, that says a shot was fired from within the vehicle. The deceased may have been on his way to grandmas for milk and cookies, but he may had an appointment with a buddy on the corner first:
http://www.newsday.com/news/nation/michael-brown-s-fatal-shooting-by-police-sparks-outcry-1.9018258
This article says that it was the deceased that assaulted the officer:
http://www.chicagotribune.com/news/chi-missouri-police-shooting-20140810-story.html
Both articles say there was a struggle for the officer’s gun after the officer was forced into the vehicle.
Being forced into the front seat would be pretty scary because of restricted space from the steering wheel and being forced into the back seat would be even scarier - locked in the vehicle away from the radio in the middle of the projects.
I”m also going to guess that, at that point, a tazer or pepper-spray would have been unuseable.
I think a ‘normal’ person would have come out of that vehicle blazing, too.
It sounds like the kid might’ve got his hands on the officer’s weapon so the officer had to resort to a back-up weapon. We’ll have to see what gets reported.