The jury in the Ana Kriegel trial has been sent home for the evening having deliberated for just over four-and-a-half hours in total.
They have been asked to consider whether two teenage boys murdered the Kildare schoolgirl in Dublin on May 14 last year.
They will also have to decide whether one of the boys is guilty of an aggravated sexual assault.
They are due to resume their deliberations tomorrow morning.
Judge tells jury prosecution case is that Ana's injuries show attacker's intent
The judge in the trial of two boys accused of murdering Ana Kriegel has told the jury that part of the prosecution case is that her attacker's intention to kill or cause serious injury is shown by the injuries inflicted on her.
Mr Justice Paul McDermott at the Central Criminal Court addressed the eight men and four women again this morning on what they will have to consider in their deliberations. He previously told them that murder arises when a person is unlawfully killed and the assailant intended to kill or cause serious injury.
He explained that an intention to kill or cause serious injury can happen in the weeks or hours leading up to an assault or at the moment of an assault.
He said that preparation can be put forward as evidence of intent, and in this case, the prosecution has said that Boy A's preparation is shown by his bringing a mask and other items in a bag to the scene.
The prosecution say that intention has been established, Justice McDermott said, and they point to the pathology and forensic evidence regarding Ana's injuries to support that.
A person is presumed to intend the "natural and probable consequences of their actions," Justice McDermott said, and the prosecution says that the natural and probable consequence of inflicting those injuries is serious injury or death.
Justice McDermott reminded the jury that the defence has said that the shock shown by the accused and the way the bag and its contents were found in a wardrobe in his room are not indicative of planning. He said if the jury has any doubt they must give it to the accused.
He further reminded the jury that anything said by one accused against the other to gardaí or anyone else cannot be used as evidence against that accused.
Justice McDermott then revisited some of the evidence of pathologist Professor Marie Cassidy, reading from the trial transcript. The jury retired to consider their verdicts at 10.46am.
The accused, who are both 14, cannot be named because they are minors. They have each pleaded not guilty to murdering the 14-year-old Kildare schoolgirl at Glenwood House, Laraghcon, Clonee Road, Lucan on 14th May last year. Boy A is further charged with Ana's aggravated sexual assault in a manner that involved serious violence to her. He has pleaded not guilty to that count also.