Since 1998, Six Mass Public Shooters were Indentified as having Schizophrenia

According to court opinions, competency rulings, law-enforcement releases, or mainstream reporting that cites those records, six U.S. mass public shooters since 1998 had a documented diagnosis of schizophrenia — 0.22 cases per year. With about two million adults with schizophrenia in the U.S. and with one over the last six years, suppose a mental health care expert was asked to identify the 1,000 most likely schizophrenics, they would be wrong at least 999 out of those guesses.

Jared Lee Loughner — Tucson, AZ (2011): court evaluators diagnosed schizophrenia; the 9th Cir. opinion notes the diagnosis explicitly.

Eduardo Sencion — Carson City IHOP, NV (2011): police information/news reports show a 1999 diagnosis of paranoid schizophrenia.

One L. Goh — Oikos University, Oakland, CA (2012): repeatedly found paranoid schizophrenia/incompetent to stand trial before later pleading; rulings and reporting reflect the diagnosis. 

Travis Reinking — Nashville Waffle House, TN (2018): trial testimony described schizophrenia (with ongoing symptoms).

Ahmad Al Aliwi Alissa — Boulder King Soopers, CO (2021): court filings/reporting state a schizophrenia diagnosis. 

Nathan Gale — Columbus, OH nightclub (2004): multiple outlets reported his mother said the U.S. Marine Corps diagnosed paranoid schizophrenia.

Schizophrenia-spectrum (closely related)

Steven P. Kazmierczak — Northern Illinois Univ., DeKalb, IL (2008): official post-incident review reported schizoaffective disorder (a schizophrenia-spectrum diagnosis)