MORGAN HILL -- Just after she arrived at the search center early Saturday, Marlene LaMar was sobbing, tears streaming down her face. She had just found out about the rope -- a ligature with her daughter Sierra's hair on it, discovered in the trunk of her accused killer's car.
"I didn't know about the rope. I had not been told," she said in anguish to supporters who surrounded and tried to comfort her before setting out on their weekly search for Sierra's remains.
While the news crushed the mother, legal analysts said the detail is a prime piece of evidence in the case against Antolin Garcia-Torres, who faces the death penalty for the kidnap and killing of Sierra LaMar, the 15-year-old Morgan Hill girl who disappeared after heading out to school on March 16, 2012.
That revelation and others surfaced in grand jury testimony -- released late Friday after this newspaper fought to make the transcript public. The evidence outlined in the 1,900-page document ultimately led to the indictment of Garcia-Torres, 23.
Steven Clark, a criminal defense attorney and former Santa Clara County prosecutor, said the rope is one of the most compelling pieces of evidence wielded by the District Attorney's Office.
"It's very problematic for the defense, especially with it also being in the trunk," he said. "The rope conjures up certain imagery of her being tied up (and) perhaps being used as a weapon."
Attorneys for Garcia-Torres did not return phone calls on Saturday.
The grand jury testimony also revealed that the prosecution's case is heavy with DNA evidence of the "trace" or "touch" variety -- bits of genetic material of unknown specific biological origin such as blood or saliva.
Bicka Barlow, a San Francisco lawyer who specializes in DNA evidence, said that kind of DNA is often used to place someone at a scene. Modern technology can detect much smaller amounts of DNA than in the past, she said.
But Barlow said it can be problematic and pointed to a recently exonerated suspect in the high-profile homicide of a Monte Sereno millionaire after it was discovered his DNA was transferred to the victim via a medical sensor that paramedics used on both the victim and the accused, who was never at the scene.
In the Garcia-Torres case, traces of his DNA were found on Sierra's discarded jeans, which led investigators to him in the first place. And a subsequent, exhaustive search of his car bolstered that connection when samples taken from an armrest, gloves and the rope revealed DNA profiles that included one matching Sierra.
"There are a lot of things in the world that people touch where they could leave DNA without realizing it," Barlow said.
However, given the details of the Garcia-Torres case, Barlow said it's difficult to see a casual connection in this situation.
Some kind of explanation for the DNA is exactly what the defense will need to come up with, said Michael Cardoza, a Walnut Creek-based criminal defense attorney with experience in DNA cases.
"Why is it there?" he asked. "What is the innocent explanation for that? With circumstantial evidence, if there are two reasonable conclusions pointing equally at guilt and innocence, you have to go with innocent. But you do need a reasonable explanation."
Testimony showed that deputy district attorney David Boyd made a case to jurors that Garcia-Torres had a chance to do just that when he was first contacted by investigators on April 4, 2012, after they found the match.
But the suspect told them that he'd never met nor seen Sierra until she became a regular face on television newscasts following her disappearance.
"They didn't go to school together," Boyd said. "They didn't go to the same gym together. They didn't have friends in common. They didn't run in the same areas."
For Garcia-Torres, Cardoza said, that was "sinking his own ship."
"As defense attorneys, we tell you: Don't talk about anything; you never know what you are going to give up to police," Cardoza said. "And that's a classic example."
DNA also comes into play in possibly the most bizarre revelation in the transcript and another incriminating statement to police. Garcia-Torres offered his own explanation to his genetic material being found on Sierra's jeans. He told them that he was a compulsive masturbator and had thrown a tissue containing his semen out of his car while driving near the spot where the girl's clothing was found.
But police had never mentioned anything about semen when they talked to Garcia-Torres about DNA, something he professed to know little about.
"They said things like fingerprint and they said things like blood," Boyd said. "It was Mr. Garcia-Torres who interjected the idea, frankly, of a sexual motive."
Boyd said that indicated what he had done to the girl.
"When you answer questions you were not asked, that is a telltale marker of a guilty conscience," said Clark, the former prosecutor.
The prosecution also spent considerable time during the two-month grand jury proceedings in the murder case on a previous Morgan Hill crime spree that Garcia-Torres is charged with. The district attorney's office believes the crimes, allegedly committed in 2009, show the suspect had a relentless drive that eventually led to Sierra's kidnapping and murder.
In those cases, nothing was taken from the female victims, and no words were spoken to indicate a robbery. Garcia-Torres allegedly tried to chase one woman down outside a Morgan Hill Safeway, then struck again with a new tactic a half-hour later at another Safeway across town -- the same supermarket where he worked.
That was a risky move, Boyd said. "But he had to do what he had to do," he added. "He had to find another target."
A stun gun used on the second victim was dropped in her car when the attacker fled, and detectives who re-examined the old cases after Garcia-Torres was arrested in the Sierra case matched his fingerprint with a battery in the device.
Boyd said the cases show a predilection for snatching women.
"Had something unusual not intervened, the defendant was going to take them to another location with their own car," he said.
Another possible defense that prosecutors discounted before the grand jury involves Sierra being missing but not dead.
Boyd said there's no evidence that Sierra would "abandon everything she knew," and family members with the search party faithful on Saturday agreed with Boyd's assessment.
"I don't think that's a possibility," Steve LaMar said of his daughter while helping out Saturday at the search center. "I know Sierra, and even if that had been the case, she would have been in contact with us by now."
Asked if he believes she is dead, tears welled up in his eyes, and he said: "I don't want to believe that, and I will hold out hope until the end."
Sierra's grandmother, Roberta LaMar, 90, said she'd heard bits and pieces about the grand jury report from her daughter Connie but not much in the way of details.
"I think she did it to protect me, but I want to know," she said. "There are things we just have to face up to. Some things are final, and there are some bad things that happen all the time."
Still, she added, "It's so hard to remember that I'll never hug her again."