Article 307 of the Dutch Criminal Code makes it an offence to cause the death of another person through one's fault (negligence). The basic offence carries a maximum of two years' imprisonment or a fine of the fourth category; where the fault consists of recklessness, the maximum is four years' imprisonment. Under settled Dutch case law, "fault" in this sense requires more or less gross or considerable negligence (aanmerkelijke schuld); slight carelessness is not sufficient. In this case the prosecution charged the defendant primarily with reckless conduct and alternatively with grossly or considerably careless, inattentive or negligent conduct. The Court of Appeal acquitted him because his conduct was not sufficiently blameworthy to reach that threshold. In cassation the Supreme Court reviewed only whether the Court of Appeal had interpreted Article 307 correctly and whether its reasoning was comprehensible, and answered both questions in the affirmative.
On 13 May 2008 the defendant was belaying the victim at an indoor climbing centre in Amsterdam. The defendant had been climbing several evenings a week for about six years without accidents, and he and the victim climbed together every Tuesday evening. On the neighbouring route the defendant's girlfriend was climbing, belayed by another person. The equipment used by the defendant and the victim was technically in order and used correctly; the belay was made with a Gri-gri device.
That evening both the defendant and the victim had climbed about ten routes. During the victim's last climb she fell three times and was each time held correctly. While belaying, the defendant occasionally talked with the belayer on the neighbouring route. Shortly after his girlfriend had been lowered to the ground, and while the victim was still about 12 metres up the wall, the defendant unclipped the rope securing the victim from his harness. He still had the carabiner in his hand when he felt a strong pull on the rope, turned round and saw the last metres of her fall. No witness saw him unclip the rope. The victim died shortly afterwards from massive blood loss caused by a tear in the right pulmonary vein; the charge also referred to multiple fractures of the sternum and ribs.
The defendant could not remember unclipping the rope. He assumed that he had done so unconsciously, apparently because in his mind he had been lowering his girlfriend and considered that remaining attached was no longer necessary once she was safely on the ground.
The prosecution argued that the defendant had failed to keep the victim in sight while she was climbing at about 12 metres, had not confined himself to his task as belayer but had talked with the neighbouring belayer and watched the neighbouring climber, and had then acted with considerable negligence by unconsciously unclipping the belay without making sure that the victim was already on the ground. In the prosecution's view, any psychological explanation of his conduct did not remove his criminal fault.
The defence argued that the defendant had acted unconsciously, as a result of automated behaviour, and relied on an article by the psychologist Professor W. A. Wagenaar submitted in a comparable earlier case. On this explanation, two automated sequences of actions had merged without the defendant noticing (a so-called "double capture slip"). The defendant also stated that constantly looking up at the climber, as the climbing-hall protocol requires, is physically impracticable and unnecessary, since an experienced belayer feels from the tension in the rope how to react.
In cassation the Advocate General at the Court of Appeal argued primarily that the Court of Appeal had misinterpreted the term "fault" in Article 307 and had thereby acquitted the defendant of something other than what had been charged, and alternatively that its reasoning was incomprehensible. Advocate General Vegter at the Supreme Court advised that the acquittal be quashed and the case referred back to the Court of Appeal.
The Court of Appeal held that belaying in sport climbing is highly dangerous and requires a high degree of care. It nevertheless found it plausible that the defendant had always been fully aware of his responsibility as a belayer and that no carelessness or negligence of any kind had been shown in performing that task. It accepted the defendant's explanation that constantly watching the climber, as the climbing-hall protocol requires, is physically impracticable for an experienced belayer, who instead reacts to the tension in the rope, and it did not regard this departure from the protocol as an aggravating circumstance. Drawing on the psychological description of automated actions, the court found that the defendant's automated belaying routine had unnoticeably switched to the routine linked to his girlfriend's descent on the neighbouring route, ending with the unclipping of the rope. The court concluded that, despite the fatal outcome, the defendant could not be blamed to the degree required for criminal liability, while noting that additional circumstances could have led to a different result.
The Supreme Court, reviewing only questions of law and the adequacy of the reasoning, held that the Court of Appeal had correctly interpreted Article 307 as requiring more or less gross or considerable negligence, and that its fact-based finding that such negligence was absent was not incomprehensible. It dismissed the appeal, contrary to the opinion of Advocate General Vegter, who had advised quashing the acquittal.
Within the Netherlands the outcome follows the settled interpretation of Article 307 of the Criminal Code, under which criminal liability for causing death requires more or less gross or considerable negligence, while slight negligence is not enough. The case was nevertheless finely balanced. The District Court convicted, the Advocate General at the Supreme Court advised quashing the acquittal, and the Supreme Court upheld it only within the limited scope of cassation review. The decision should also be read narrowly. The courts did not hold that an automated error can never be blamed on a belayer; they held that, on these facts and without aggravating circumstances, the lapse did not reach the Dutch threshold of criminal fault. Dutch legal commentary (Zeilstra, Verkeersrecht 2013/81) notes that the belayer could still be held liable in civil law, where fault is assessed more objectively.
Internationally the decision is exceptional, as a comparison with other cases in the database shows. In the Czech case 6 Tdo 425/2019, an experienced belayer using a Gri-gri was convicted of causing grievous bodily harm by negligence after the rope slipped through the device, and the court derived his duty of care from the methodology of the Czech Mountaineering Association. The Dutch Court of Appeal, by contrast, accepted the belayer's departure from the climbing-hall protocol (not watching the climber constantly) as compensated by his experience and did not treat it as an aggravating circumstance. In the German civil case OLG Hamm 9 U 124/13, a belayer who released the rope brake before the climber had called for it was held liable, the court stressing that a belayer on the ground can and must concentrate exclusively on belaying. A comparable lapse thus led to liability in Germany and the Czech Republic, but not to criminal liability in the Netherlands.
For the climbing community the case shows that even experienced belayers are vulnerable to routine-based slips, especially when distracted by activity on neighbouring routes, and that relying on individual vigilance alone is not enough. Whether such a slip leads to criminal liability depends largely on the threshold of fault in the relevant jurisdiction, which differs considerably across Europe.
