The U.S. Supreme Court Wednesday unanimously rejected provisions of a Maine law that restricts the shipment of tobacco products in the state.

"Despite the importance of the public health objective, we cannot agree with Maine that the federal law creates an exemption," Justice Stephen Breyer wrote in the court's majority opinion. "The act says nothing about a public health exception."

The ruling determines that federal trucking laws bar state regulation of tobacco shipments, despite Maine's concern that tobacco products might be shipped to minors.

The state law, passed by Maine in 2003, required shippers such as United Parcel Service Inc. (UPS) to follow special handling procedures when delivering cigarettes or other tobacco products with the aim of keeping tobacco from being shipped illegally to minors. The industry challenged the provisions, arguing they were onerous, increased costs and ran afoul of the federal limit on state shipping regulations.

Major shipping companies, including UPS and FedEx Corp. (FDX), already have voluntarily agreed not to ship cigarettes in a settlement with New York over tobacco restrictions enacted in that state.

In previous legal action, the Maine law was struck down by a federal trial court. The 1st U.S. Circuit Court of Appeals in Boston affirmed lower-court rulings that held federal shipping laws pre-empted the Maine law. The Supreme Court's opinion affirms the appeals court holding.