Morrison Waite,
Munn v. Illinois — Opinion of the Court
“ The controlling fact is the power to regulate at all. If that exists, the right to establish the maximum of charge, as one of the means of regulation, is implied. In fact, the common-law rule, which requires the charge to be reasonable, is itself a regulation as to price. Without it the owner could make his rates at will, and compel the public to yield to his terms, or forego the use.But a mere common-law regulation of trade or business may be changed by statute. A person has no property, no vested interest, in any rule of the common law. ”
