For nearly three decades, Owens served as the official executioner at Oklahoma State Penitentiary, carrying out 65 state-sanctioned executions — a tenure that places him among the most prolific figures of his kind in American penal history. His inclusion here stems not from any single act but from the accumulated weight of that role, compounded by ten additional killings outside his official capacity.

A trained psychiatrist who became the political architect of ethnic cleansing campaigns during the Bosnian War, he directed policies resulting in the massacre at Srebrenica and the prolonged siege of Sarajevo — among the most consequential atrocities on European soil since World War II. His conviction by the ICTY on charges of genocide and crimes against humanity marked one of the most significant war crimes verdicts of the post-Cold War era. The twelve years he spent evading capture, working quietly under an assumed identity in Belgrade, underscore how extensively he was sheltered after the war's end.