It’s a chicken or egg kind of thing. Did drug use trigger schizophrenia or did the schizophrenic use drugs to self medicate.
I don’t know that this behavior of shooting the dog is more a bizarre behavior (in the mental health sense) rather than debauched behavior in the drug and alcohol fueled loss of reason and moral capacity sense.
My experience with schizophrenics (either as family or clients) is that they are usually only dangerous when they feel threatened or cornered and they can’t plan their way out of a wet paper bag. This shooting was too organized and has elements of depraved thought rather than disorganized or confused thought.
I think that the schizophrenia is usually already there but at a level where it isn’t interfering with daily life. Once the drug use begins the lid gets blown off and it looks like the drugs caused the disease. But who knows, really.
The shooting was certainly planned and depraved, but it also looks like she didn’t have any sort of reason for doing it. The senselessness of it makes me suspect that it’s craziness acting itself out.