Rick Kammen, an attorney for Nashiri, argued that the explanation for why Harithi was killed could bolster the defense’s case if his role was significantly greater than Nishiri’s.
The prosecution said it had already turned over all documents it considered relevant.
Nishiri faces the death penalty in the Guantanamo Bay military tribunal for his role in the Cole attack.
His pre-trial hearing comes a week after the latest round of pre-trial hearings were held at Gitmo for alleged 9/11 mastermind Khalid Sheikh Mohammed and four others.
After skipping the tribunal Tuesday, the judge ordered Nishiri to attend Wednesday’s session.
Nashiri complained about the chains that were used to transport him to and from the court.
"Security must have a limit," he told the judge, according to reports. "I do intend to attend all future sessions. But if the guards do not treat me better, I have the right not to come. I let the world know that the judge sentenced me to death because I didn't show up to court due to chains. Thank you."