He had to be allowed to kill for the left to push their political ends of disarming the populous. Arresting someone for threatening to kill doesn't increase government's power over us.
I seems to me I’ve heard this scenario many times before.
Authorities had someone who was clearly in a violent state of mind and made threats to society.
So they bring them in, talk with them and then let them go.
Wind ‘em up and watch ‘em go.