Because criminals don't stroll down the street with their gun in the open.
But unfortunately, crazy people do. Crazy people are not a rarity anymore, I see any number of disturbed or dysfunctional people on a weekly basis. You don't know what they're capable of, given the opportunity. Schizophrenics, developmentally disabled, emotionally disturbed, PTSD's - and bad things can happen when they stumble across uncle Zeke's old hunting rifle in the back of the family closet.
I have lived 20+ years in rural Iowa. Over a decade in NW Indiana and Chicago area. Nearly ten years in California. I have seen a few long guns in pickup truck rear windows, but I have NEVER seen a man walking down a residential street with an uncased long gun. My guess is that 90% of all American's experience in that regard is similar to mine. The key here is that it was not cased. If it had been simply in a zippered case, odds are that there would be no controversey here. School shootings happen. Mall shootings happen. Playground shootings... HAPPEN. But the rifle would have to come out of the case before mayhem could ensue. As long as it's in the case, you are one step removed from unleashing death and destruction, and that one step is all it takes for most folks to cut you the benefit of the doubt. But take it out of the case, and at that point folks are going to want - no NEED - to know just what your intentions are.
Regardless of the technical legallity of his actions, carrying a long gun uncased (and to all appearances, loaded) is bound to stir up anxiety in your average residential neighborhood. People with a sense of social responsibility may be inclined to want to cut a fellow some slack in thinking that he MAY be just transporting his rifle, and didn't have a case - BUT are they willing to take that chance that he is not a crazy person with harm on his mind? Now mind you, a pistol open carried BUT IN A HOLSTER is a different matter because it is in a holster and not in your hands as if you intend to use it here and now. I think a person who has a sense of responsibility for his family and the lives of his neigbors has a responsibilty to have the situation checked out. The proper people to do this sort of checking is the police.
Now, I think it's unfortunate that they feel like they have to charge the guy with "disorderly conduct" and most likely that was a political decision. However, look at it from a different perspective. The guy is displaying what (apparently for this jurisdiction, at least) is abnormal behavior while in posession of a firearm. The cops have to roll wheels even if it is just to cruise by and say "Dude, what's up with the rifle?" and find out he's just headed to his friend's house down the street to show him a new gun. How many of these types of calls before it becomes a drain on police resources? So, they try to discourage this type of thing and hope word gets around - if you're going to transport a rifle, out of public courtesy, please use a case.
You may have a right to free speech, but would you expect to be held accountable if you yelled "fire" in a crowded theater? Sure, you have a right to say what you want, but if you carelessly act in a way that legitimately causes distress in others, you haven't acted responsibly. And for that, you can and should be held to account.
