The family of teacher Ann Maguire have lost their challenge against a coroner's decision not to call evidence from pupils who had contact with her schoolboy killer immediately before the murder.
Mrs Maguire's husband Don, children and nephews - who were not at London's High Court for the ruling on Monday - wanted Mr Justice Holroyde to order the decision taken by assistant West Yorkshire coroner Kevin McLoughlin to be reconsidered.
An inquest into Mrs Maguire's death is due to take place before a jury at Wakefield Coroner's Court in November.
The 61-year-old teacher was stabbed in the back by 15-year-old Will Cornick as she taught a Spanish class at Corpus Christi Catholic College in Leeds in April 2014.
Cornick was later sentenced to life with a minimum term of 20 years.
Dismissing the claim for judicial review, the judge said: "I have much sympathy for the claimants, and I fully understand their reasons for wishing to pursue this line of inquiry.
"For the reasons I have given, however, I am unable to accept the submission that the assistant coroner reached a decision which was so seriously flawed as to be ...unreasonable."
Counsel Nick Armstrong told the judge that it was the only occasion on which a teacher had been killed by a pupil in a British classroom and the family were anxious "that all the lessons that can be learned from this enormous tragedy are learned".
He said the coroner accepted that the inquest should address school rules and policies about weapons in school, reporting the presence of weapons in school, and how those rules and policies had been communicated to students.
This was because that over the three hours before the murder, Cornick told other students what he intended to do, and showed a number of them the knife - yet no report to a member of staff was made, at least until it was too late.
The coroner said that all those students - now adults - were "potentially vulnerable" and were not to be re-approached, with the result that only transcripts of their interviews with police at the time would be adduced.
Mr Armstrong said this approach was unlawful as the decision was a blanket one based on limited and generic evidence about vulnerability generally.
Cathryn McGahey QC argued that the decision was lawfully open to the assistant coroner who was "uniquely well-placed" to make it.
The request to call the former pupils was opposed by other interested parties - including the sisters of Mrs Maguire, one of whom was an experienced teacher - who were concerned about the effect that giving evidence might have on these young people, she added.
And Leeds City Council had said the facts regarding the morning of the incident were already clear and required no duplication of inquiry.
Ms McGahey said: "The key issue was the usefulness of the evidence that these students could give.
"The coroner was entitled to reach the view that the benefit of calling the students would be limited."
It was a school without a history of violence and therefore without any reason for there to be any express but unwritten rule or policy.
Most of the students told the police they had not taken Cornick's threats seriously and the transcripts of their contemporaneous interviews would be available.
The evidence of teaching staff, who had experience of the attitudes of hundreds of students of varying ages, was likely to be far more reliable and useful.
ogi Amin, partner at law firm Irwin Mitchell, said: "Ann Maguire's family will now take stock and discuss the options with their legal team.
"They remain committed to finding out the truth and exactly what happened on the day Ann was killed through a thorough, open and fair process.
"They believe it is the only way that lessons will be learned from the incident."