Negligence – Causation. There was no significant doubt that the judge's finding had been that the failure to warn had been a freestanding cause of the fall over a tripping point and a laser gun smashing against his front teeth causing serious injury in the 'but for' sense. The Queen's Bench Division, in dismissing the appellant's appeal against the judge's finding of negligence, further held that the judge had had the advantage over the court of hearing the respondent's evidence and forming a view of how he would be likely to respond to a warning.