French teen sentenced to 18 years for fatal stabbing of school supervisor
The boy, who was 14 at the time of the attack, had been held in custody for the past 13 months.
As a minor, he faced a maximum sentence of 20 years.
During a two-day hearing in the town of Chaumont, prosecutors argued he should be held fully responsible.
But the court ruled that his judgement had been impaired at the time because he was suffering from a "persecutory delusion", the presiding judge said.
However, the court refused to reduce his sentence because of the "extreme seriousness" of the crime and because he had shown "no empathy, remorse or regret".
It also ordered 10 years of judicial supervision after his release, including compulsory psychiatric treatment.
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'A logical decision'
The sentence, which matched the prosecution's request, was applauded by relatives and friends of the victim – 31-year-old Mélanie Grapinet.
"It's a judgment that reflects the seriousness of the facts," lawyer Édouard Charlot-Jacquard, who represents the victim's family, told reporters.
But it "will not erase the family's pain, who came to these two days of hearings with great dignity, seeking justice without hatred or revenge".
Grapinet's mother said: "I will never be satisfied, I have lost my daughter, but today I am going to start breathing a little again, at least for her."
She said the teenager had shown "no regret, no emotion, no feelings, nothing. It was two days from hell".
Antoine Chateau, the teenager's lawyer, described the verdict as "a logical decision both in view of what happened during the hearing and of my client's statements and behaviour".
A separate hearing on compensation for the victim's family is due on 7 September.
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Seven stab wounds
Grapinet was stabbed seven times outside Françoise-Dolto secondary school in Nogent – a town of about 3,500 people in the Haute-Marne department 300kms east of Paris, on 10 June 2025. The victim, who was also a local councillor, died at the scene.
The attack happened in front of numerous witnesses as police conducted a random bag check outside the school, looking for knives.
During police questioning, the boy said he had no "particular grievance" against the teaching assistant but wanted to attack "any" school supervisor.
Investigators said he had begun planning the attack a few days earlier after another supervisor had told him off for kissing his girlfriend at school.
French government to ban knife sales to minors after deadly school attack
The killing, which came amid a series of knife attacks in French schools, prompted widespread attention, with President Macron condemning a "senseless wave of violence".
Following the attack, French police began carrying out more regular bag checks at schools as part of a crackdown on knife violence.
In 2025, French schools carried out more than 6,000 random bag checks over two months, leading to 186 knives seized and 32 students taken into police custody.