In the case of Pennsylvania R. R. Co v. Hughes (1903), the U.S Supreme Court ruled in favor of the defendant, Hughes, who was injured while working for Pennsylvania Railroad Company due to negligence on part of a fellow employee and sought compensation from his employer under federal law. The court held that employers are liable for injuries sustained by their employees as a result of negligence by other employees within the same company during work hours, even if those negligent acts were not directly related to their employment duties or responsibilities at that time. The ruling emphasized that an employer's responsibility extends beyond providing safe conditions and equipment; it also includes ensuring safety from harmful actions or neglects committed by co-workers during work hours regardless of whether they are performing their assigned tasks or not at that moment. This decision significantly expanded workers' rights and protections against workplace accidents caused by colleagues' carelessness, thereby setting a precedent in labor law cases involving similar circumstances.

In the dissenting opinion for Pennsylvania R. R. Co v. Hughes, Justice Harlan disagreed with the majority's decision to deny compensation to Mrs. Hughes for her husband’s death caused by a train accident while he was working on the railroad tracks as an employee of Pennsylvania Railroad Company (PRR). He argued that PRR should be held liable because it failed in its duty of care towards Mr. Hughes by not providing him with a safe workplace and adequate warning about incoming trains, which directly led to his fatal accident. The justice believed that employers must bear responsibility when their negligence results in harm or death of employees; thus, they should compensate victims or their families accordingly even if there is no explicit contract stating such obligations between them.