(CNN) Dylann Roof, the white supremacist convicted of killing nine black parishioners at a Charleston, South Carolina, church, suffers from numerous mental disorders, according to an unsealed court document.

The December 6 document was filed by his legal team on the eve of opening statements in his federal trial in an effort to convince the court to make certain accommodations for their client.

His lawyers cited a competency hearing in which a doctor determined Roof has "social anxiety disorder, a mixed substance abuse disorder, a schizoid personality disorder, depression by history and a possible autistic spectrum disorder."

The disorders hamper Roof's ability to stand trial, his lawyers contend, saying the effects include:

difficulty processing multiple sources of information

"excessive focus on non-essential details"

difficulty retaining information when required to focus on multiple things

"an extreme need for predictability and routine"

anxiety when things can't be predicted

a tendency to be easily overwhelmed

"Without some accommodation," the lawyers said, "the defendant's disabilities will impair his ability to participate in his trial," in violation of the Fifth, Sixth and Eighth amendments.

Among the accommodations requested were routine breaks, shortened court days or weeks, two days' notice before witnesses are called and permission to request breaks when Roof felt overwhelmed.

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The doctor's full competency evaluation remains under seal.

Roof, who is white, is the first person to get the death penalty for a federal hate crime. He also faces state murder charges.

In November, a judge halted jury selection in the case to allow time for Roof to undergo a competency evaluation. Roof was ruled competent to stand trial, represent himself and be sentenced.

The 22-year-old in December requested that the judge reinstate his legal team for the guilt phase of the trial. He asked to represent himself again during sentencing.

"There's nothing wrong with me psychologically," Roof told jurors ahead of sentencing . "Anything you heard from my lawyers in the last phase, I ask you to forget it."

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Before the jury deliberated his fate for three hours, Roof told the jury he still feels he had no choice but to kill nine people at the Emanuel African Methodist Episcopal Church in June 2015.

"In my confession to the FBI I told them that I had to do it, and obviously that's not really true. ... I didn't have to do anything," he said. "But what I meant when I said that was, I felt like I had to do it, and I still do feel like I had to do it."

That lack of remorse, a key factor in doling out the death penalty, matched sentiments from his journal

"I am not sorry. I have not shed a tear for the innocent people I killed. I do feel sorry for the innocent white children forced to live in this sick county. I do feel sorry for the innocent white people that are killed daily at the hands of the lower races," he wrote.