(CBS) U.S. authorities in Afghanistan failed to advise John Walker Lindh of his legal rights and ignored his pleas for a lawyer, his defense attorneys contend.

The lawyers are seeking to bar use of his statements in the trial of the American-born Taliban soldier.

"The suppression issue is the whole ballgame in this case," said CBSNews.com Legal Analyst Andrew Cohen. "If Lindh's lawyers convince the judge that what their client said to the government in early December should not be heard by a jury because it was improperly obtained, the government's case probably falls apart. It's a tough enough case with Lindh's statements — without them it's virtually non-existent."

The government has acknowledged Lindh's statements last December were relied on heavily in his indictment, which charged him with conspiring to murder Americans and aiding the Taliban and al Qaeda. It could be a major setback to prosecutors should the motion succeed.

The issue will be argued on July 15. A hearing Monday is on the motions to dismiss the various counts.

According to a criminal complaint filed in the case, Lindh told the FBI he personally met with Osama bin Laden at a training camp and learned from an instructor about June 2001 that bin Laden had sent people to the United States to carry out suicide operations.

The written pleading raised the unique issue of a U.S. citizen's rights when he's questioned abroad as a captured soldier, and not yet brought into the criminal justice system.

Lindh's motion discounted his signature on a form waiving his rights to a lawyer when he was questioned by an FBI agent in Afghanistan. He was carried to the interrogation while blindfolded, shackled and bound to a stretcher after spending two days in a metal shipping container with neither heat nor light, the motion said.

The defense tackles the Miranda questions involving the military for the first team, reports CBS News Correspondent Stephanie Lambidakis, claiming the military totally failed to administer his rights.

"The law is clear that any statements elicited without Miranda warnings cannot be used against Mr. Lindh in this criminal proceeding," the motion said.

"The government does not contend that any warnings were provided to Mr. Lindh prior to Dec. 9, 2001. "Therefore, any statements allegedly made by Mr. Lindh ... prior to that date ... must be suppressed."

As proof they cite military instructions sent to the Special Forces telling people only to ask about intelligence matters, not criminal matters. They quote a JAG (Judge Advocate General) commander instructing "that if Lindh said anything incriminating, read him his rights."

The defense also says Lindh was found in a small room, perhaps 10 by 10 feet, with 15 dead or dying persons on the floor.

The filing Friday includes new pictures of Lindh with duct tape over his eyes. Another photo shows for the first time the bullet removed from Lindh's leg some 15 days after he was captured.

If you add all of this up, the defense says, the "government cannot meet its burden of demonstrating a valid waiver" of his rights against self-incrimination. And they say Lindh was "completely intimidated, broken mentally and physically. His only thought under the circumstances was how he could get relief from the tortuous conditions under which he was being held. Clearly that meant doing whatever his captors asked him to do."

Under the Supreme Court's Miranda decision, a suspect should be advised he has the right to remain silent, anything he says can be used against him in court, he has the right to have an attorney during questioning and a lawyer would be provided if he couldn't afford one.

Lindh asked for a lawyer on several occasions and was told by interrogators none were available, the motion said, adding he was not informed that his parents retained counsel for him in the United States.

Lindh was questioned by military interrogators between Dec. 1 and Dec. 8.