Are Mass Murderers Insane? Usually Not, Researchers Say

Analyzing his database, Dr. Stone has concluded that about 65 percent of mass killers exhibited no evidence of a severe mental disorder; 22 percent likely had psychosis, the delusional thinking and hallucinations that characterize schizophrenia, or sometimes accompany mania and severe depression. (The remainder likely had depressive or antisocial traits.)

One hundred percent
of mass murderers had guns.
They all had guns. Guns.
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