Dylann Roof
CHARLESTON, SC - JULY 16: Dylan Roof (C), the suspect in the mass shooting that left nine dead in a Charleston church last month, appears in court July 18, 2015 in Charleston, South Carolina. The Associated Press, WCIV-TV and The Post and Courier of Charleston are challenging a judge's order issued last week that prohibits the release of public records in the June 17 shooting at Emanuel African Methodist Episcopal church. (Photo by Grace Beahm-Pool/Getty Images)

Dylann Roof is appealing his death sentence related to the 2015 fatal shooting of nine Black parishioners inside an historic Charleston, S.C., Black church.

In a legal brief filed with the 4th U.S. . Circuit Court of Appeals in Richmond, lawyers for the White supremacist say that Roof was suffering from mental illness at the time of the fatal shooting at Mother Emanuel AME Church, the New York Daily News is reporting.

In the documents, the lawyers say a number of issues may have “tainted” Roof’s trial and have asked that the court review them. The lawyers allege that Roof “believed his sentence didn’t matter because White nationalists would free him from prison after an impending race war.”

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The lawyers argue that Roof was suffering from schizophrenia and other psychological ailments when he acted as his own lawyer at his trial, the Associated Press is reporting. 

Before his trial in 2017, a judge ruled after a competency hearing that Roof was competent and had an extremely high IQ, WCSC reports. Roof represented himself at trial and was convicted on 33 federal charges. He was prosecuted under the federal Shepard/Byrd Hate Crimes Act and is first person to be ordered executed for a federal hate crime. Roof is on death row at the federal penitentiary in Terre Haute, Indiana.

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On the evening of June 17, 2015, Roof, then 22, disrupted a bible study meeting taking place at the church and opened fire. Those killed were church pastor and South Carolina state Sen. Clementa Pinkney, Cynthia Graham Hurd, Susie Jackson, Tywanza Sanders, Ethel Lance, Rev. DePayne Middletown-Doctor, Rev. Daniel L. Simmons Sr., Rev. Sharona Singleton and Rev. Myra Thompson.

At the time of his conviction in January 2017, Roof showed no emotion but then requested that his standby counsel be replaced because he did not trust him, WCSC reported.

Mother Emanuel was founded in 1817 and is the oldest African Methodist Episcopal church in the South.