In County of Kankakee v. Aetna Life Insurance Company, the Supreme Court of the United States was asked to decide whether a county could tax the income of a life insurance company. The company argued that the tax was unconstitutional because it was a direct tax on the company's income, which was prohibited by the Constitution. The Court held that the tax was not a direct tax, but rather an indirect tax on the company's business activities. The Court reasoned that the tax was not a direct tax because it was not imposed on the company's income, but rather on its activities. The Court also held that the tax was not a violation of the Constitution because it was not a direct tax on the company's income. The Court concluded that the tax was a valid exercise of the state's power to tax. The Court's decision was unanimous.

The dissenting opinion in County of Kankakee v. Aetna Life Insurance Company argued that the majority's decision was wrongfully decided and should be overturned. The case centered around a dispute between the county and an insurance company over whether or not the county had to pay for certain bonds issued by it, which were backed by insurance from Aetna. The dissent argued that under Illinois law, when a bond is insured with an approved insurer like Aetna, then any losses incurred due to default on those bonds are covered by the insurer - regardless of what other laws may say about who must bear responsibility for such losses. Furthermore, they asserted that since this was clearly stated in both state statutes as well as contracts between parties involved in issuing these bonds, there could be no doubt as to who would ultimately have to bear responsibility if something went wrong - namely Aetna itself. As such, they concluded that the court should reverse its ruling and find in favor of Kankakee County instead.