In the case of Farson, Son & Company v. Bird, as County Treasurer of Shelby County, Alabama in 1918, the U.S. Supreme Court was tasked with determining whether a tax assessment by Shelby County on bonds owned by Farson, Son & Company violated the Fourteenth Amendment's due process clause. The company argued that since they were based in Illinois and only had an agent operating within Alabama to collect interest on their behalf from local borrowers who held their bonds as collateral for loans made outside Alabama state lines; therefore they should not be subject to taxation there. However, the court ruled against them stating that because these securities were physically present within Alabama and produced income there through interest payments collected by an agent residing in-state; thus it constituted sufficient connection or nexus for taxation purposes under existing jurisprudence interpreting what constitutes "property" for tax purposes under Fourteenth Amendment protections.

In the dissenting opinion for Farson, Son & Company v. Bird, it was argued that the majority's decision to uphold Alabama's tax law violated principles of equal protection under the Fourteenth Amendment. The justice contended that by taxing bonds issued out-of-state at a higher rate than those issued within Alabama, the state effectively discriminated against interstate commerce and imposed an unfair burden on non-residents. This unequal treatment contradicted constitutional guarantees of uniformity in taxation and infringed upon federal authority over interstate commerce. Furthermore, they disagreed with the majority’s view that this case was similar to previous cases where differential tax rates were upheld because those involved tangible property located within a state’s borders rather than intangible assets like bonds which are not tied to any specific location.