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(1951) 95 SJ 655 (CA). An employer's duty to this employees to provide competent co-workers (see employers liability) is onerous (see HudsonVRidgeManufacturing1957), but not absolute. In this case, the claimant was a trainee, who was injured by a violent practical joke played upon him by his fellow trainees. The Court of Appeal held that the employer could not have been expected to forsee an act of deliberate wrongdoing on the part of the culprits, and were thus not liable for it.