The papers also confirm the government contention that Reid "was not unassisted in his efforts to destroy Flight 63." Reid was ruled out as the source of a human hair and palm print found in the bombs, the documents said.
On Monday, FBI Director Robert Mueller said the FBI now believes that "an al Qaeda bomb maker" constructed the shoe bomb.
According to prosecutors, Reid said he picked a U.S. carrier flying over the Christmas holidays, knowing that if his shoe bomb went off, Americans would stop flying again, and the American economy would be damaged.
Reid, 28, a British citizen, is charged with attempting to blow up an American Airlines flight from Paris to Miami on Dec. 22. Passengers and crew members restrained him after he allegedly tried to light a fuse protruding from his shoe. The flight was then diverted to Boston.
CBS News Correspondent Jim Stewart reports Reid's mother may also have some more explaining to do. She met with reporters in London a week after her son's arrest.
"Other than what I've heard or read in the media, I have no knowledge of this matter," she said.
But according to court papers, Reid is quoted in e-mails to his mother before the attempted attack as telling her he was doing it not because he wanted to die, but because it was his duty as a Muslim to "help remove repressive American forces."
The information was included in documents filed by prosecutors in U.S. District Court in Boston in response to a motion to lift restrictions on Reid's communications with his defense.
In their memorandum, prosecutors said Reid wrote in an e-mail to his mother Dec. 20 that "what I am doing is part of the ongoing war between Islam and disbelief, (and as such a duty upon me as a Muslim).
"The reason for me sending you (a document he calls his "will") is so you can see that I didn't do this act out of ignorance nor did I just do it because I want to die, but rather because I see it as a duty upon me to help remove the oppressive American forces from the Muslim land and that this is the only way for us to do so as we do not have other means to fight them," Reid wrote. The spelling and punctuation are consistent with the court documents.
Reid faces charges of attempted murder, attempted homicide and attempted use of a weapon of mass destruction in the incident, which further unnerved air travelers just months after the Sept. 11 attacks.
Reid, who faces a maximum of life in prison if convicted, has pleaded not guilty in the case, which is tentatively scheduled to go to trial in November.
The new glimpse at the case being built against Reid came as prosecutors asked the court to maintain limits on the communications between the Briton and his lawyers.
In March, a judge ordered Reid's lawyers to keep secret the substance of their conversations with him because of concern they could contain hidden messages.
Reid's lawyers have asked the judge to lift some of the restrictions, but prosecutors on Thursday argued that doing so could jeopardize national security.
"There is a danger that even the most honorable of individuals might become the inadvertent, unknowing and unwitting conduit for the transmission of nefarious messages, even when there is good-faith belief that such communications are being made in pursuit of a client's defense," they said.