fellow-servant rule

This rule proceeds on the theory that the employ e, in entering the service of the principal, is presumed to take upon himself the risks incident to the undertaking, among which are to be counted the negligence of fellow servants in the same employment, and that considerations of public policy require the enforcement of the rule. But this presumption cannot arise where the risk is not within the contract of service, and the servant had no reason to believe he would have to encounter it.