"Adult" is an arbitrary and ambiguous term.
Indeed. And I'm fully aware the State of Michigan does not recognize a 15-year-old as an adult with rights to use that gun. My comment is that he usurped the role of an adult, and as such, reaped the consequences of adult actions.
It would be the same for a youth stealing a car, using it in a drive-by shooting, or vehicular homicide.
Legal right and adult action are not the same.
Some will say that driving is a privilege and not a right, if that were to be true then the state could on a whim deny some that privilege.
Many feel it is a right. It never has been. But, the State does not act on whims, but law, including magistrates.
All of the ages when certain rights are allowed are based upon a "one size fits all" sort of reasoning that is a consensus of the majority of law makers. However, anyone that has dealt with teens would tell you that there are outliers in every age group.
But that is also true of adults of many years past the age of majority. The law and its definitions are not customized. A mother is a mother. A husband is a husband. An adult is an adult, barring legal conservatorship.
This is when parental responsibility is most important. But, what about a home that is only a house? It seems that a teacher should be able to detect a child that is neglected.
All I can say is, having between 60-120 kids a day and a full schedule in class doesn't leave a lot of time for emotional surveys. This is high school. The kids are moody, hyper, angry, silly, mouthy, lazy, bored, indifferent, and 100 other things in one week. Some wear their feelings on their sleeves. Others are a wall. Imagining that teachers are like Room 222 is a bit wishful.
Many kids hit high school and are abashed at the brutality of it, not only from their peers, but often from teachers who don't know them and don't make any particular effort to show care.
A teacher reported the boy who shot up the school for his drawings. The boy hid his back pack, his parents left him in school. The police were not brought in until it was too late.
His parents, from the two trials, certainly appeared to be hostile to authority, and particularly to school administration. They represent a significant element in society that breeds malcontentment. It is not exactly shocking that their mentality was partly to blame for the youth deciding to act out.
Most school shootings happened with a surprise element, this one did not. There was a huge red flag, the system really screwed up.
These should result in changed laws, just as maritime disasters do. The colossal failure at Uvalde is likely going to eventually result in some change in law enforcement response. All these are different. All these are alike.