Discharging a firearm within city limits tends to be a state by state and then city by city ordinance. I know Tennessee has great news clips from time to time about it.
Not showing the scale of the rover is inexcusable! Thank you for mentioning it.
Here are some people next to it: http://en.wikipedia.org/wiki/File:Mars_Science_Laboratory_wheels.jpg
Finally got around to posting something today. Such fun.