Yep, that's often the local prosecutor's response. In this case, though, the shooter/passenger was seated in the car when the carjacker accosted the driver. Both were presumably standing alongside the car, giving the shooter a clear shot at the perp's lower half. He's just lucky that he wasn't facing the other way; he might've received a centerfire catheter.
The article doesn't say which of the five shots the shooter scored with; I'd suspect she got him with the first shot and then continued to fire at a moving (retreating) target.
I'll bet her ears are still ringing, too.