The charge is based on circumstantial evidence because LaMar's body has never been found, though DNA evidence found on LaMar's jeans has a high statistical probability of linking Garcia-Torres. The defense disputed that claim.
LaMar's father has maintained a daily presence in court. Her mother took the witness stand early in the trial. In court, they sat just a few feet from the man accused of killing their daughter, separated by a railing.
Prosecutor says most damaging DNA evidence in Antolin Garcia-Torres case is #SierraLaMar hair on rope found in his trunk & glove w/her DNA. pic.twitter.com/i993yDxbT6
— David Louie (@abc7david) May 2, 2017
"Obviously this jury has seen Sierra LaMar's family in the courtroom. They've seen support for Mr. Garcia-Torres, and they know this is the highest stakes case we have in society. It's a big burden on this jury," explained legal analyst Steve Clark.
The jury of six women and six men is expected to begin deliberations on Friday. The defense starts its closing argument on Wednesday.
RELATED: Anniversary marked of Sierra LaMar disappearance
Clark thinks their strategy will be, saying, "The defense is going to portray here as a distraught teenager, unhappy at home who ran away and could still be alive."
This morning, the prosecution reiterated over and over again that it was unreasonable to think Lamar would run away without telling friends or connecting on social media, saying there was no hidden life of Sierra Lamar.
Roger Nelson, a search leader for Sierra LaMar, has been in court for most of the trial. "Ultimately, everybody would like to have the same result, and that is justice for Sierra and also the return of Sierra to a loving family," he said.
The jury must decide if Garcia-Torres is guilty beyond a reasonable doubt. Members of the volunteer search team, who hoped to find Sierra or her remains, still harbor bitterness.
"To be in that position as a young, young girl like that, defenseless, and have this big monster on top of you, hurting you. It's frightening," said Mary Doering, another search volunteer.
If convicted, Garcia-Torres could face the death penalty if convicted.
Click here for more stories on Sierra LaMar.
Prosecutor calls argument "absurd" by defense that Antolin Garcia-Torres' DNA was transferred several times by others to #SierraLaMar jeans.
— David Louie (@abc7david) May 2, 2017
Prosecutor David Boyd breaking down evidence in digestible segments to remind jury of salient points before they deliberate. #SierraLaMar pic.twitter.com/tVI0tYJ915
— David Louie (@abc7david) May 2, 2017
Prosecutor telling jury #sierralamar is dead absent a body. Points out her social media went dark on 3/16/12; her clothing discarded.
— David Louie (@abc7david) May 2, 2017
Prosecutor David Boyd tells jury, "Sierra LaMar is dead. (Antolin Garcia-Torres) has one hurdle - each & every one of you." #sierralamar
— David Louie (@abc7david) May 2, 2017