ALEXANDRIA, Va. (AP) — The Justice Department said it would be able to try accused Sept. 11 conspirator Zacarias Moussaoui in a civilian court while protecting his rights and government secrets.

The need to protect both Moussaoui's rights and sensitive national security information makes the case complex, but "should not breed skepticism about the propriety of prosecuting this case," the government told a federal judge Monday.

The written pleading reaffirmed Attorney General John Ashcroft's objection to moving the case to a military tribunal, even though some Pentagon and intelligence officials reportedly would prefer that option. A tribunal could provide for greater secrecy and fewer defendant's rights than a civilian trial.

The department's pleading responded to a stark warning nearly two weeks ago from U.S. District Judge Leonie Brinkema, who said she was disturbed by the government's "shroud of secrecy" toward Moussaoui and questioned whether his case could proceed in a public judicial forum.

"The government is fully confident that the court will be able to try this case consistent with the demands of the law," the prosecutors said.

The judge ordered the government to respond to Moussaoui, who is representing himself and complained he was not receiving enough information to craft a defense.

Moussaoui is not entitled to classified documents, and has made his defense more complicated by not cooperating with court-appointed lawyers who have security clearances and have seen the secret material.

Nonetheless, the pretrial arguments have evolved into a clash between a defendant's constitutional right to information that could help his defense and the need to safeguard national security.

Prosecutors argued they have turned over all the unclassified material that Moussaoui is entitled to have, noting that only unclassified documents would be used in a trial.

"He is not entitled to a preview of the government's theory in this case, or as the defendant put it, to the government's 'opening statement' to the jury," the brief said.

Brinkema, in addition to questioning the government's secrecy toward the defendant, has also ruled that Moussaoui can have access to at least one al-Qaida prisoner, suspected Sept. 11 coordinator Ramzi Binalshibh. Moussaoui has asked Brinkema for access to other prisoners, including the alleged mastermind of the attack, Khalid Shaikh Mohammed.

Prosecutors have appealed that order, reportedly arguing such access could harm a sensitive interrogation.

If the government loses in the 4th U.S. Circuit Court of Appeals, the odds could increase for dropping the current charges and allowing the military to assume the prosecution role before military judges.

Moussaoui is the lone defendant in the United States charged as a conspirator with the Sept. 11 hijackers and could face the death penalty if convicted. He has admitted belonging to al-Qaida but denied he was part of the Sept. 11 plot.

Moussaoui complained the government has changed the theory of its case, and asserted he was wrongly kept in the dark because the theory is classified.

Moussaoui said the government switched from calling him the 20th hijacker to describing him as the "fifth pilot," suggesting an additional attack by air beyond the four planes that were hijacked and crashed on Sept. 11, 2001.

The government said Moussaoui's comments about a change in theory "are as irrelevant as they are inaccurate."

"Contrary to defendant's assertions, the government has never described the defendant in the indictment or any pleading as the '20th hijacker,'" the government contended.

"Instead, the indictment alleges that the defendant was part of a conspiracy to kill Americans by flying hijacked commercial airliners into buildings. And, while the charged conspiracy resulted in the September 11 attacks, and the murder of nearly 3,000 innocent victims, the indictment does not, because it need not, outline a particular theory of the defendant's guilt."

In a separate pleading, Moussaoui's court-appointed lawyers supported a request by media organizations to open proceedings and release court documents to the public.

The public "cannot know, for example, except by speculation, about the novel constitutional propositions being advanced by the government," the motion said. It added that without more openness, the constitutional concerns of Moussaoui and the public "will continue to take a serious beating."