Unless the court can conclude on the whole record that the total effect of the law as a safety measure in reducing accidents and casualties is so slight or problematical as not to outweigh the national interest in keeping interstate commerce free from interferences which seriously impede it the court must uphold the statute.
The Illinois Splash Guard statute violated the Commerce Clause because it placed an unconstitutional burden on appellees, interstate carriers, and had a deleterious effect on interstate commerce. Appellees, interstate carriers, challenged the constitutionality of the Illinois Splash Guard statute on the grounds that the statute conflicted with statutes of other states and that the statute burdened and obstructed interstate commerce because it made the conventional mudflap illegal in Illinois. The appeals court enjoined appellant director of the Department of Public Safety of Illinois from enforcing the statute on the ground that it violated the Commerce Clause, and the Court affirmed that decision on certiorari.
Is the Illinois contested statute constitutional?
The Court held that the local safety measure balanced against the burden on commerce violated the Commerce Clause because the mudflap design was so out of line with the requirements of almost all other states that appellees assumed a great burden to comply with the statute; the inconsistency of mudflap designs delayed interstate commerce and inconvenienced appellees who were forced to seek ways to comply with the statute.