Bell's Gap Railroad Company v. Pennsylvania was a case heard by the Supreme Court of the United States in 1883. The case involved a dispute between the Bell's Gap Railroad Company and the Commonwealth of Pennsylvania over the taxation of the railroad's property. The railroad argued that the taxation was unconstitutional because it violated the Fourteenth Amendment's Equal Protection Clause. The Supreme Court disagreed and held that the taxation was constitutional. The Court reasoned that the taxation was based on a rational basis and did not discriminate against the railroad. The Court also held that the taxation was not a taking of the railroad's property without just compensation, as the railroad had argued. The Court concluded that the taxation was a valid exercise of the state's power to tax and did not violate the Fourteenth Amendment. The decision in this case established the principle that taxation must be based on a rational basis and must not discriminate against any particular group or individual.

In Bell's Gap Railroad Company v. Pennsylvania, the Supreme Court of the United States was asked to decide whether or not a state could impose taxes on railroad companies operating within its borders. The majority opinion held that states have the right to tax railroads in order to raise revenue for public purposes and that this power is not limited by any constitutional provision. Justice Field dissented from this decision, arguing that such taxation would be an unconstitutional interference with interstate commerce and thus violate both Article I of the Constitution as well as other provisions protecting free trade between states. He argued further that if each state were allowed to tax railroads operating within their borders it would lead to a patchwork system of taxation which would be detrimental both economically and politically, leading ultimately to chaos rather than harmony among the various states.