In Hoiness v. United States (1948), the Supreme Court ruled on a case involving the interpretation of federal tax law. The petitioner, Mrs. Hoiness, was seeking to deduct from her income taxes payments she made under a separation agreement with her former husband. She argued that these were alimony payments and therefore deductible under Section 22(k) of the Internal Revenue Code. The government disagreed, arguing that because Mrs. Hoiness had agreed to make these payments as part of a property settlement rather than as support for her ex-husband, they did not qualify as alimony and could not be deducted. The Supreme Court sided with the government in this case. It held that only those payments which are made for spousal support or maintenance can be considered alimony and thus deductible from income taxes; any payment made as part of an overall division or distribution of marital property does not fall within this category.

In the dissenting opinion for Hoiness v. United States, Justice Jackson argued that the majority's decision to allow a wife to sue her husband under federal law was inconsistent with common law principles and state laws prohibiting such suits. He contended that this ruling would disrupt domestic relations and create unnecessary litigation between spouses. Furthermore, he expressed concern about the potential implications of allowing federal courts to intervene in matters traditionally governed by state family law. In his view, it was not within Congress' intent or constitutional authority to regulate personal relationships between husbands and wives through tort claims brought under federal maritime law.