Dear Science,

I'm just floored that the recent cop killer was out and about on the streets despite being so obviously crazy. What the hell? Shouldn't homicidal maniacs who think they're Jesus Christ and meticulously plan executions of cops be kept locked up indefinitely? Can being crazy really cause people to do all these things?

In Fear of Crazy

Mental illness, at its core, is a derangement of conscious thought. As such, the sort of crazy that we're dealing with in people like Maurice Clemmons is a uniquely human illness.

Consider schizophrenia. It's a sort of inability of the brain to accurately sort out what's going on in the world. For most of us, our brains do a very good job of sifting through the patches of information gleaned from our senses—forming a coherent and generally accurate representation in our minds of what is really going on. Think of how the eyes work, rapidly scanning the space around us, only resting for a moment at any given spot. Our brains have to interpret this jumble into some sort of coherent sense of where we are and what is around us.

For those with the various kinds of schizophrenia, the mind can start responding to self-generated information (hallucinations, voices, and the like), misinterpretations of what is being sensed, and a general failure to integrate all this into a coherent sense of what's going on. With this can come a diminished ability to respond back to the outside world, leading to flat faces, an inability to interact with others, a detachment from the surrounding world, or an inability to even generate a coherent chain of thoughts. In this jumble, strange beliefs (e.g., that you're Jesus Christ) can become fixed in the malfunctioning mind.

Schizophrenia is more common than you'd expect. The lifetime risk of being diagnosable with schizophrenia is about 0.5 percent. Doing the math, we could expect about 3,000 people in Seattle, and 32,000 statewide, to have schizophrenia. But being schizophrenic does not make you automatically dangerously violent. While those with schizophrenia are more likely than the general population to commit violent acts, it's not clear that the disease is causal. And people who are confused and unable to properly respond to their environment are far more likely to harm themselves than to harm others.

Drugs and treatments exist for the disease. A strong social safety net and appropriate, stable, and controlled housing can help those with mental illnesses live their lives peacefully. Of course, all of the above were dismantled by a process starting during the Reagan administration as a means of saving money. We're still paying a steep price for these savings.

Compassionately Yours,


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