John Mark Karr, the schoolteacher suspected in the 1996 slaying of 6-year-old JonBenet Ramsey, met with two attorneys ahead of his first appearance in a Boulder courtroom.

Deputy public defender Seth Temin and Steve Jacobson, a retired public defender, spent about three hours at the jail Sunday, declining to answer questions as they left.

Karr was expected to be in court Monday for a hearing expected to last only a few minutes, with Karr advised of his rights and any charges against him.

Temin has been aggressive in his short time on the case, winning approval of a gag order and making sure prosecutors and anyone else comes through him to talk with Karr.

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Jacobson is considered a DNA specialist, and DNA could be one of the major issues should Karr go to trial. Temin has already challenged any DNA that may have been taken from Karr as illegally obtained.

In a court filing, prosecutors said they have evidence that has not been disclosed despite a decade of public scrutiny of the case.

The best-case scenario for prosecutors would be slam-dunk DNA evidence linking Karr to the Ramsey's former home, where JonBenet's beaten and strangled body was found by her father on Dec. 26, 1996.

Without it, experts say, it's much more difficult to build a strong murder case against the 41-year-old Karr, who has said he was there when the girl died but stopped short of an outright confession.

"In this day and age of shows like 'CSI' jurors not only want forensic evidence before they will convict a person, they demand it," said Robert Hirschhorn, a jury consultant based in Dallas.

Forensics expert Henry Lee and former prosecutor Bob Grant, both involved in the Ramsey investigation, have said some of the DNA collected at the scene was mixed or contaminated.

Investigators have said DNA was found in blood spots on JonBenet's underwear, but a Ramsey family attorney said two years ago it didn't match any of the 1.5 million samples in an FBI database at the time. Other DNA recovered under the girl's fingernails is degraded, Grant said.

Other physical evidence includes a ransom note, the garrote used to strangle the girl, a boot print found outside the Ramsey house and some indications an intruder could have entered through a basement window.

JonBenet's parents, John and Patsy Ramsey, were initial targets of a grand jury investigation that ended with no indictments. Patsy Ramsey died in June after learning authorities had turned their attention to Karr, who was living in Thailand when he was detained earlier this month.

Scott Robinson, a Denver attorney familiar with the case, said prosecutors may end up attacking the police investigation for the alleged contamination of the DNA evidence.

Prosecutors can overcome police mistakes with solid work, said Grant, a former Adams County district attorney who served as an adviser on the case in the 1990s.

"I've never seen a case in trial where the defense didn't find something to attack the investigation about in terms of technical investigative techniques, and I've never seen an investigation that was perfect," Grant said. "If there's DNA able to be matched to him, then the mistakes are of little or no consequence."

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