So the 18 year old, armed with an automatic weapon suited best for military use, is fully acquitted of murder. So be it. I respect jury verdicts. But there are people who question why a teenager would be allowed to possess such a weapon of war and intervene with it in public, apparently with the apparent approval of citizens of Wisconsin. Yes, under the law he is acquitted by the jury, but the rest of the common sense world outside are asking how a teenager is allowed buy such a weapon, and what were the the parents thinking (if they even knew what he was doing).
I believe that Epicurus would raise questions of upbringing and education, and the absence of police on the spot to keep the peace and deter teenage hotheads and others.
At 18 I, too, had a sub-machine gun. The difference was that I was in the army, properly trained, super-conscious of the dangerous weapon hanging by my side,in a dangerous environment, but under the watchful eye of a sergeant-major who had served in the Second World War.