Congress passed an act punishing transportation of lottery tickets across state lines.
Champion (P) was caught doing this, and argued that this cannot be constitutionally regulated by Congress.
Procedural History
SCOTUS found for Ames (D), upheld law as unconstitutional.
Issues
Is a law forbidding transportation of lottery tickets across state lines unconstitutional?
Holding/Rule
Lottery tickets are subjects of traffic, and therefore of commerce, and the regulation of the carriage of such tickets from state to state, at least by independent carriers, is a regulation of commerce among the several states.
Reasoning
While it is said that the authority given to Congress was not to prohibit but to regulate (from Hammer), the power of Congress to regulate is plenary, is complete in itself, and is subject to no limitations except the 10th Amendment.
If a state considering lottery legislation can take into account the evils of raising money in that way, why can't Congress also decide that it doesn't want commerce to be polluted by lottery tickets and regulate it?
If it be said that the act is inconsistent with the 10th Amendment, the answer is that the power to regulate commerce among the states has been expressly delegated to Congress.
As a state may prohibit the sale of lottery tickets, so can Congress prohibit the carrying of lottery tickets from one state to another.