To begin with, the Isla Vista shooting seemingly was premeditated and was done out of malicious motives as much as it arose from mental illness. The perpetrator of that shooting suffered from sociopathy, a different and sinister form of mental illness. Apparently, he wasn't out of touch with reality and instead wanted to get even.
The incident of a few years back in which Peter Cuckor was killed with a flower pot resembled more a situation of a mentally ill person who was disoriented and didn't know what he was doing.
Police are apparently trained to protect themselves when they believe their lives are threatened, and unfortunately this is sometimes lethal for someone who appears to be a threat. That might be what happened in Half Moon Bay, although I do not know much about that incident.
How can more of these killings be prevented? I don't know. I don't think we should undo the decades of progress that have been made to at least somewhat safeguard the human rights of persons with mental illness. Maybe part of the answer is to make conditions better for people.
Concerning heart disease, stroke, and diabetes, there are specific risk factors that can sometimes predict someone getting these illnesses. Could people study mental illness in a more scientific manner to discover the environmental variables that might lead to getting a mental illness?
A difficult childhood isn't necessarily a predictor of mental illness. Many people have had rough childhoods and have gone on to become great people, or at least normal.
The fact is we don't know enough about the development of the human brain. We don't know exactly why some people's minds split off from reality and make someone psychotic. We don't have a scientific method for predicting this kind of violence. Why are some people with mental illness nonviolent while others are violent? Are videogames making people ill? I don't know.
In fact, I am quite ambivalent about mental health law. People need help, and some may need to be forced into treatment. But I think this must be done in a way that assures humane and competent treatment.
We should get treatment for those who need help, but we should not undo the progress that was made by people who suffered the abuses that existed in the 1950's, 60's and 70's. And, we should not ignore the fact that there is a lot of room for improvement in current medications, most of which pose significant health risks. People are dying young due to the metabolic side effects of medications.
When someone can voluntarily undergo available mental health services, it is a far more valuable thing than just forcing people. I believe people can be trained to have more insight concerning their condition.
And finally, hope must be offered--the hope of some sort of better life than just looking forward to your next cigarette.