Chapter 4
The authority of the federal government to regulate interstate commerce has, at times, come into conflict with state authority over the same area of regulation. The courts have tried to resolve these conflicts with reference to the police power of the states.
Police power refers to the residual powers granted to each state to safeguard the welfare of their inhabitants. Examples of areas in which states tend to exercise their police power are zoning regulations, building codes, and sanitation standards for eating places. However, there are times when the states’ use of police power impacts interstate commerce. If the exercise of the power interferes with, or discriminates against, interstate commerce, then the action is generally deemed to be unconstitutional. The limitation on the authority of states to regulate in areas that impact interstate commerce is known as the dormant commerce clause.
In using the dormant commerce clause to resolve conflicts between state and federal authority, the courts consider the extent to which the state law has a legitimate purpose. If it is determined that the state law has a legitimate purpose, then the court tries to determine whether the impact on interstate commerce is in the interest of the citizens of the state, and will rule accordingly. For instance, an ordinance that banned spray paint, issued in the city of Chicago, was challenged by paint manufacturers under the dormant commerce clause, but was ultimately upheld by the U.S. Court of Appeals because the ban was intended to reduce graffiti and related crimes.