There are certainly scary homeless people; psychopathy is one of many reasons one might become homeless. But beware of publication bias - mentally ill homeless

There are certainly scary homeless people; psychopathy is one of many reasons one might become homeless. But beware of publication bias - mentally ill homeless people are far more likely to draw your attention than either sane homeless people or someone who screams in their own living room a lot. Your well-housed neighbor isn't necessarily a lot more sane or well-behaved, and certainly not less violent I've read. Diseases of inflammation are on the rise, and depression and Schizophrenia increasingly look like brain inflammation. (These don't correlate with excess violence to others, however.)