SANTA CLARA (CBS SF) — A Santa Clara County Superior Court judge Thursday again postponed a plea hearing for the defendant in the Sierra LaMar kidnapping and murder case after the defense said it could not access some digital copies of evidence.

Judge Sharon Chatman rescheduled the hearing for April 18 so the defense counsel for Antolin Garcia Torres could review all evidence provided on compact discs by investigators, Deputy District Attorney David Boyd said.

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Boyd said that there were “technical problems” with some of the discovery information placed on discs by the Santa Clara County Sheriff’s Office and passed on to the defense.

“When you are producing hundreds of CDs, some get corrupted,” Boyd said after Thursday’s hearing in San Jose.

The discs include police photos and videos of interviews with witnesses that will be used to bolster the prosecution’s case against Garcia Torres, charged with kidnapping and murdering Sierra.

Sierra, 15, was last seen leaving her home outside Morgan Hill for school on March 16, 2012.

Garcia Torres, 21, who has not yet entered a plea, did not appear in court Thursday and had his attorney represent him at the hearing.

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He was being held without bail in Santa Clara County Jail.

Sierra’s body has not been found but prosecutors believe she was murdered.

Sheriff’s deputies arrested Garcia Torres on May 21 and prosecutors charged him with killing the teen after detectives found DNA believed to be Sierra’s inside his red Volkswagen Jetta.

After the hearing, several supporters of Sierra expressed frustration with how long the proceedings have taken and pointed out that it has been more than 10 months since Garcia Torres’ arrest and he has still not entered a plea.

“They’ve had a whole year to assemble this,” said Tom Barrett, of Morgan Hill, who has participated in searches for Sierra that take place each Saturday.

San Jose resident Renee Figueroa, another volunteer searcher, said of Garcia-Torres, “He wants his rights—she has no rights.”

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