The story is legit.
Judge rejects slave trauma as defense for killing
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Noting the theory has not been proven or ever offered in court, Washington County Circuit Judge Nancy W. Campbell recently threw out DeGruy-Leary's pretrial testimony.
But the judge said she would reconsider the defense for Bynum's September trial if his lawyer can show the slave theory is an accepted mental disorder with a valid scientific basis and specifically applies to this case.
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I don't really have any comment. Some bozo creates a theory out of whole cloth and some attorney picks it up because his client is otherwise well on his way to a 25-year stint in an ass-pounding penetentiary (they love child abusers in the big house).