A more thorough explanation:

The fellow-servant rule is a legal principle that states that an employer is not responsible for the injuries caused by one employee to another employee due to negligence.

For example, if an employee is injured because a coworker was careless, the employer is not liable for the injury under the fellow-servant rule.

However, this rule has been changed by workers' compensation laws in most states.

In some places, employees were considered fellow servants if they were working towards the same goal. In other places, the "superior servant rule" or the "doctrine of vice principal" was used to determine if an employer was responsible for an employee's injury caused by another employee who had control or direction over them.

For instance, if a manager instructs an employee to do something that results in injury to another employee, the employer may be held responsible under the superior servant rule.