DNA evidence, considered a potential key to solving the 1996 slaying of 6-year-old JonBenet Ramsey, has emerged as an early battleground in the case against John Mark Karr.

Karr's public defender, Seth Temin, said Friday that any DNA samples taken from his client could not have been legally obtained. He asked a judge to prohibit prosecutors and police from conducting any DNA testing without first notifying the court and the defense.

"Biological evidence reveals highly private and sensitive information about a person," Temin wrote. "Mr. Karr's right to privacy can only be protected by giving him the opportunity to be heard on this issue prior to collection of a sample."

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District attorney's spokeswoman Carolyn French said prosecutors would respond after reviewing Temin's court filings. There won't be much public comment: Boulder County District Judge Roxanne Bailin issued a gag order forbidding attorneys and authorities from publicly discussing most aspects of the case.

Karr's first appearance in Boulder County Court is scheduled for Monday. He has not been formally charged in JonBenet's death.

After JonBenet's father, John Ramsey, found her body in the family's basement on Dec. 26, 1996, police collected DNA from blood spots in her underwear and from under her fingernails.

Investigators have said some of the DNA was too degraded to use as evidence, but some was of sufficient quality to submit to the FBI in 2003. The sample did not match any of the 1.5 million samples in the agency's database at the time, according to the Ramsey family attorney.

Karr, 41, was given a mouth-swab DNA test while he was in Thailand, a law enforcement official who spoke on condition of anonymity because of the ongoing investigation has told The Associated Press. The results of that test were not known.

Temin suggested Karr would not provide DNA samples without a court order. After meeting with Karr, he said he did not know whether authorities had actually obtained any DNA samples.

Temin, who spent at least four hours at the jail Friday, refused to disclose what they discussed. When asked how his client was doing, Temin responded: "How's anyone in jail doing? It's a very difficult place to be. It's very challenging."

The public defender also asked the judge to seal a sample of Karr's handwriting from public scrutiny. Some commentators have suggested that Karr's handwriting in a high school yearbook resembles the writing on a ransom note found in the Ramsey home a few hours before JonBenet's body was discovered.

JonBenet was found strangled and with a skull fracture. Authorities once said her parents were under "an umbrella of suspicion," but prosecutors never charged anyone in the case.

Boulder District Attorney Mary Lacy has refused to say what led to Karr's arrest, and persuaded a judge to seal the reasons she had Karr detained last week on charges of first-degree murder after deliberation, felony murder, first-degree kidnapping, second-degree kidnapping and sexual assault on a child.

Karr told authorities and reporters in Thailand he was present when JonBenet died, but no one has publicly placed him in Colorado at the time of the crime.

"Despite what may have been disclosed to the public over the many years since the crime, most of the evidence in the affidavit has not been disclosed, nor has the media developed it independently," Assistant District Attorney William Nagel wrote in a court filing.

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