In the 1999 case of Hunt-Wesson, Inc. v. Franchise Tax Board of California, the U.S Supreme Court ruled in favor of Hunt-Wesson (now part of ConAgra Foods), stating that California's method for taxing income from other states was unconstitutional. The issue at hand was whether a state could tax income earned outside its borders if it also allowed companies to deduct interest expenses related to earning that income. The court held that this practice violated the Commerce Clause because it discriminated against interstate commerce by double-taxing out-of-state earnings while only single-taxing in-state earnings. This decision clarified how states can tax corporations with business operations across multiple jurisdictions and set an important precedent regarding state taxation powers under federal law.

In the dissenting opinion for Hunt-Wesson, Inc. v. Franchise Tax Board of California, Justice Ginsburg disagreed with the majority's interpretation of federal tax law and its application to state taxation practices. She argued that the majority had misapplied previous case law by not considering a key distinction between business and nonbusiness income in their analysis. According to her, this oversight led them to incorrectly conclude that California's method of taxing multinational corporations was unconstitutional under federal law because it did not provide a fair apportionment of taxes based on where income was earned. Instead, she contended that California’s approach properly distinguished between business and nonbusiness income as required by existing precedent and should have been upheld.