Stefany, who is diabetic, told federal jurors that she had been in the deposition for several hours and had not eaten. Her lawyer had requested a break, she said, but Brown's attorney said he was nearly done and showed her the e-mail.
Stefany said she was not thinking clearly and had read only the first line when she said she had written it.
She said in federal court that she was in shock when Brown's attorney then read aloud the entire e-mail and its racist contents during the deposition.
The entire e-mail was not read aloud in court Monday, but an excerpt read by Brown's attorney was critical of interracial relationships and attributed the e-mail recipient's support of Brown to her race.
Stefany testified that while the e-mail purportedly came from her, it had no header to show where it originated, was not typed in the format she always used, and contained language she had never used.
"I did not write it," she said firmly.
Stefany said she believed the e-mail was fabricated by cutting and pasting from a message she had sent.
"I didn't think anyone could stoop that low," Stefany said.
When William M. McSwain, one of Brown's attorneys, continued to press the point that Stefany had said during the deposition she was the author, she bristled and said she had explained what had occurred during the deposition.
"I think this is pretty pathetic, that this is the best you can come up with for a defense," Stefany told McSwain.
She said that even if she had written the e-mail, it would not contradict all of the evidence prosecutors have introduced against Brown in the fraud trial.
Brown has been charged with defrauding Agora and three other charter schools she founded and then participating in a scheme with two other former administrators to cover it up.
Last month Stefany asked U.S. District Judge R. Barclay Surrick to quash her subpoena to testify as a defense witness. The judge canceled a scheduled hearing on whether Stefany could be compelled to testify when she agreed to appear.
Stefany is the lead defendant in a pending defamation suit Brown and her Cynwyd Group L.L.C. management firm filed in 2009 against several former Agora parents.
Cynwyd Group subcontracted with K12 Inc. to provide management and technology for Agora.
To settle several civil suits, Brown and Cynwyd severed all ties with Agora. K12, a for-profit firm in Herndon, Va., still manages Agora and dozens of cyber schools across the country.
McSwain also asked Stefany about an e-mail she sent to the Agora board in late 2009 after Brown was no longer involved.
In that e-mail, Stefany wrote that she felt the parents being sued by Brown had been used by K12 to get rid of Brown and then left "hanging in the wind."
Stefany said that she sent the e-mail and that it reflected the anger she felt at the time. She testified that she did not know whether K12 had set out to use the parents to force Cynwyd Group out of its contract with Agora but that K12 had benefited from the outcome.
Closing arguments begin Tuesday morning.