In the case of Tully et al. v. Griffin, Inc., 1976, the U.S Supreme Court was tasked with determining whether a New York State tax credit violated the Import-Export Clause of the Constitution. The clause prohibits states from imposing taxes on imports or exports without Congress's consent. The state had enacted legislation that provided a tax credit to businesses for every gallon of beer produced within its borders and sold in other states or countries but did not offer this same benefit to out-of-state breweries selling their products in New York. Griffin Inc., an out-of-state brewery, argued that this constituted a violation as it effectively imposed higher taxes on imported beers compared to those brewed domestically. The court ruled in favor of Griffin Inc., stating that while technically structured as a tax credit rather than an import duty, it still functioned as such by creating economic protectionism which disadvantaged interstate commerce - thus violating both the Import-Export Clause and Commerce Clause.

In the dissenting opinion for Tully et al. v. Griffin, Inc., Justice William J. Brennan Jr., joined by Justices Byron White and Thurgood Marshall, argued that the majority's decision to uphold New York's tax credit system was incorrect because it violated the Commerce Clause of the U.S Constitution. The dissenters believed that this law unfairly discriminated against interstate commerce by providing a greater benefit to companies operating solely within New York than those conducting business across state lines. They contended that such preferential treatment could lead to economic protectionism and balkanization, undermining national unity and free trade among states - principles at the heart of our federal system as envisioned by framers of constitution.