Dylann Roof, the first person to be sentenced to death under the federal hate-crimes act, has appealed his conviction for the 2015 killing of nine black worshipers at a historic church in Charleston, S.C.

In a 321-page legal brief filed Tuesday with the Fourth U.S. Circuit Court of Appeals, his lawyers argued that when Roof represented himself in court, he “was a 22-year-old, ninth-grade dropout” who suffered from schizophrenia, autism, anxiety and depression.

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