Wrongdoers can do no wrong. Good guys are not good for business. All power is best left to Government and VIPs, no exceptions. That's the Lefty mindset, and much of the Right is only a fake, token opposition and compromise. Many gun owners have fingers to the wind on their opinions too.
The nice Marysville LE don't want to prosecute
because of any bystander dangers or ordinances. They want to use bystander dangers or ordinances as a justification to prosecute
because they feel threatened by citizen rights and powers. Which we are obviously are losing.
I don't love people opening fire in parking lots. In general I think LE are best suited to make arrests and stop crimes in progress when they are available, willing, and not under directions to look the other way. But I don't think shoplifting, thuggery, and driving into people is a non issue, and I know well that civilians aren't the only shooters to worry about:
http://nation.time.com/2013/09/16/ready-fire-aim-the-science-behind-police-shooting-bystanders/