Cars are deadly weapons too
I'm sure this question will be debated for a while, and it's entirely appropriate for the authorities to carefully review the situation and ask if the level of force directed at Carey was justified. But as a matter of general principle, I don't think it's automatically wrong to use deadly force against someone evidently intent on committing vehicular homicide. An "unarmed" person driving a car is armed, and dangerous. And of course, there's no real way of knowing who you're up against in the heat of the moment, and what kind of weapons they might be packing.
It's sadly comical, but not unexpected, to watch the media interest in the story diminish as soon Carey's identity and lack of firearms were established. Once again, the big story here is about mental illness, not "gun control." One can well imagine what coverage would look like if she was an armed white member of the Tea Party. Okay, let's go for broke and make her a male armed white member of the Tea Party. Imagine the "national conversation" we'd be having right now!