In the case of Clyde Mallory Lines v. Alabama Ex Rel. State Docks Commission, 1935, the U.S Supreme Court ruled in favor of Alabama's State Docks Commission. The dispute arose when Clyde Mallory Lines, a private shipping company operating out of Mobile Bay in Alabama, objected to paying wharfage fees imposed by the state-run docks commission on all cargo loaded or unloaded at its facilities. The company argued that these charges were unconstitutional as they violated both interstate commerce and equal protection clauses since not all shippers using the port had to pay them. However, Justice Cardozo delivered an opinion for a unanimous court stating that there was no violation because it was within states' rights to charge reasonable fees for use of their harbor facilities and such charges did not interfere with interstate commerce nor violate equal protection laws if applied uniformly.

In the dissenting opinion for Clyde Mallory Lines v. Alabama, Justice Stone argued that the majority's decision to uphold Alabama's tax on out-of-state shipping companies was inconsistent with previous rulings of the Court and violated principles of interstate commerce. He contended that this ruling allowed states to discriminate against foreign corporations in favor of local businesses, which he believed contradicted established constitutional law. Furthermore, he expressed concern over potential economic implications if other states followed suit by imposing similar taxes on out-of-state businesses operating within their borders. This could lead to a patchwork system where each state has its own set of rules and regulations for interstate commerce, potentially stifling business growth and development across state lines.