In the United States v. Healey case of 1895, the Supreme Court ruled on a matter concerning customs duties. The defendant, Healey, had imported iron from Belgium and was charged with paying import taxes based on its weight. However, he argued that according to an existing treaty between the U.S and Belgium at that time (1861), such imports were exempted from taxation. The government countered this argument by stating that Congress had passed laws in 1883 and 1890 imposing duties on such goods regardless of any prior treaties. The court sided with the government's interpretation of law over international agreements or treaties; it held that while a treaty may indeed be considered as supreme law of land under Constitution’s Article VI clause II, it is not invulnerable to subsequent legislation by Congress which can modify or repeal provisions within them. Therefore, even though there might have been a valid treaty providing for tax exemption when it was signed back in 1861; later legislative acts effectively nullified those specific terms related to taxation policy within said agreement - thereby making Mr.Healey liable for payment as per updated tariff rates.

In the dissenting opinion for United States v. Healey, Justice Brewer argued that the court majority had erred in its interpretation of the law and its application to this case. He contended that it was not within Congress's power to regulate commerce between states in such a way as to prohibit certain goods from being transported across state lines. In his view, this exceeded their constitutional authority and infringed upon individual rights. Furthermore, he disagreed with the majority's assertion that alcohol could be classified as a dangerous substance under federal law; instead, he believed it should be considered an ordinary article of commerce subject only to reasonable regulation by individual states rather than outright prohibition by federal authorities. This disagreement stemmed from differing interpretations of both congressional powers under the Commerce Clause and principles of federalism more broadly.