Joseph McKenna, Western Union Telegraph Company v…
“ Such a statute was plainly a regulation of interstate commerce, and exhibited in a conspicuous degree the evils of such interference by a state, and the necessity of one uniform plan of regulation. The statute of Michigan has no such objectionable qualities. It imposes no additional duty. It gives sanction only to an inherent duty. It declares that in the performance of a service public in its nature, that it is a policy of the state that there shall be no contract against negligence. ”
