WASHINGTON -- Lawyers for the man convicted of killing Washington intern Chandra Levy said in documents unsealed Tuesday that his prosecution was "predicated on a lie," and that they intend to file a motion for a new trial.

The statements made by attorneys for Ingmar Guandique were included in approximately 200 pages of documents related to hearings held in December and January. Reporters and the public were not permitted to hear the discussion between the judge and lawyers because prosecutors argued that making the hearings open would endanger a witness.

The decision to close the proceedings was challenged by media organizations including The Associated Press. The judge in the case said some material would be unsealed.

The records show that government prosecutors asked to seal the Dec. 18 hearing to talk about information they learned about after Guandique was sentenced. Defense attorneys say the information calls into question the testimony of one witness and "drastically undercut" the government's case.

More than 20 witnesses testified for the prosecution during the trial. The original case hinged on a jailhouse informant who said Guandique had confessed to killing Levy. The unsealed documents show prosecutors learned a year ago about a problem with a witness but it's not clear if that person was the informant.

The Levy case was one of the most high-profile trials in Washington in years when it began in 2010. Levy, a 24-year-old intern for the U.S. Bureau of Prisons, disappeared in 2001 after leaving her apartment in jogging clothes.

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The case attracted particular attention because of her romantic relationship with Gary Condit, then a California congressman. Her remains were found in 2002 in a heavily wooded area of Washington's Rock Creek Park. Guandique, an illegal immigrant from El Salvador, was ultimately convicted of her murder and is serving a 60-year prison sentence. He said when he was sentenced that he had nothing to do with her killing.

The documents unsealed Tuesday include transcripts from hearings on Dec. 18 and Jan. 4. They also include court documents filed by prosecutors and Guandique's defense attorneys. Significant portions of the records are blacked out, sometimes for pages.

"Mr. Guandique and the public have a right to know precisely what happened at Mr. Guandique's trial and why the government allowed its prosecution to be predicated on a lie," Guandique's attorneys argue in a motion unsealed Tuesday.

A transcript also shows John Anderson, one of Guandique's attorneys, said during the January hearing that the defense plans to file a motion to dismiss the indictment and request a new trial.

In a document filed with the court, defense attorneys compare the Guandique case to the prosecution of the late Sen. Ted Stevens of Alaska, whose 2008 conviction on corruption charges was vacated after the Justice Department admitted withholding evidence from the defense.

It wasn't clear, however, that the new information would have been admissible at trial. The unsealed transcripts seem to show that during the hearing in December, a government prosecutor, Fernando Campoamor, told the judge "it would have been litigated whether it could have been used at trial, and if so, to what extent it could have been used at trial." A defense attorney, James Klein, said that was "astounding."

The transcripts also show attorneys wrestling with the closure of the proceedings. The defense had wanted them to be open, but the judge sealed the hearings after prosecutors argued that a witness' personal safety would be endangered if they were public. The defense has said prosecutors were not specific about the threats the witness would face.

The last hearing in the case was Thursday and its transcript was not released. The judge has scheduled another hearing for April 11.

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Secret hearings held in killing of Washington intern Chandra Levy

Family photo via AP

Chandra Levy, a 24-year-old grad student from the University of Southern California, went missing in 2001 after completing a federal internship.

The 2001 slaying of Washington, D.C., intern Chandra Levy is back in court, but behind closed doors: Records show a judge has been holding secret hearings in the case of the man convicted of killing her, according to The Associated Press.

Hearings have been held for the past several weeks, with neither prosecutors nor defense lawyers revealing their purpose, according to court records obtained by AP. The next hearing will be on Feb. 7 in D.C. Superior Court; The AP and several other media organizations are petitioning to open the proceedings.

Ingmar Guandique was convicted of first-degree murder in November 2010, nine years after Levy's disappearance and death, despite no DNA evidence linking him to the crime, and a lack of witnesses.

Levy's father, Robert Levy, told KGO-TV in San Francisco that he has not been told what's been happening in the secret court hearings. He said Guandique was a "convicted rapist and an illegal alien." 

But, he added, "if he's innocent of murder, he shouldn't be in jail for it." 

Jacquelyn Martin / AP file

Ingmar Guandique, seen in 2009.

Police had initially questioned then-California Rep. Gary Condit -- who Levy was romantically tied to -- in their search for suspects, before determining he wasn’t involved. The following year, when Levy's remains were found in a Washington national park, authorities charged Guandique, who was already in prison for attacking female joggers in the same park, reported The AP.

Levy's case stole the attention of the national media. Condit was never charged, but his political aspirations were ruined nonetheless.

Prosecutors had requested a life prison sentence for Guandique, an illegal immigrant from El Savador. Instead, he was given a 60-year sentence, which he is currently serving.

After he was sentenced, Levy's mom, Susan, asked him if he was the one who killed her daughter, and he shook his head.

"Mr. Guandique, you are lower than a cockroach," she told him at the time, according to The AP.

The Associated Press contributed to this report.