A jury has gone out to consider its conclusions in the inquest into the death of teacher Ann Maguire, who was murdered in her classroom by a 15-year-old student.
Mrs Maguire was 61 years old and had taught at Corpus Christi Catholic College, in Leeds, for more than 40 years when Will Cornick stabbed her multiple times during a Spanish lesson on April 28 2014.
A jury of six women and five men has heard how Cornick stabbed her seven times with a 34cm long kitchen knife.
One of the blows went all the way through the teacher's body and one severed her jugular vein.
Mrs Maguire is the only teacher ever to be murdered by a pupil in a UK school.
The inquest heard how, on the morning of the attack, Cornick told a number of children what he planned to do and also how he wanted to kill two other teachers at the school.
He showed four of these pupils at least part of the knife he had in his bag.
Much of the inquest has focused on why none of these children reported what they had heard before the tragedy.
Coroner Kevin McLoughlin told the jury he had taken a decision not to call the teenagers to give evidence.
Mr McLoughlin told the jurors they needed to consider whether the fact that the children did not report what they heard and saw contributed to Mrs Maguire's death.
He said: "It's a matter for your judgement."
Mr McLoughlin said the jury also needed to consider whether the school's lack of an explicit policy about not bringing knives onto the premises contributed to the death.
But the coroner warned the jury that they should not speculate and that contributory factors needed to be more than "minimal, trivial or negligible".
He said it may be that the jury felt identifying such contributory factor as the lack of a school rule might "dilute the stark reality" of what Cornick did.
Summing up the evidence, Mr McLoughlin said the devastation caused by Mrs Maguire's murder on her family had been "self-evident".
The coroner said "the cruelty is unspeakable" as he reminded the court that Mrs Maguire had adopted her sister's two sons after her death.
He said these two men had now lost both their natural and adopted mothers.
Mrs Maguire's husband, Don, told the jury last week how he simply wanted all the evidence to be examined in detail.
Mr Maguire said that this had not happened because there had been no crown court trial, as Cornick pleaded guilty, and no serious case review.
He also criticised the Learning Lessons review carried out in the wake of the tragedy by the Leeds Safeguarding Children Board.
The company director said the "narrative" that there was nothing in Cornick's actions before the attack that could have warned anyone about what he was about to do needed to be challenged so lessons could be learned for the future.