Hunt-Wesson, Inc. v. Franchise Tax Board of California
The Court ruled that California's tax rule, which cut a company's interest-expense deduction by the amount of dividend and interest income it received from an unrelated out-of-state business, was unconstitutional.
Because the rule effectively taxed income California had no constitutional power to tax, it violated the Due Process and Commerce Clauses, and the Court sent the case back for further proceedings.
How it got here: The California Court of Appeal upheld the tax rule, the California Supreme Court denied review, and the U.S. Supreme Court agreed to hear the case.
The Case in Depth
What happened
Hunt-Wesson, Inc. is the successor to a company that did business in California and elsewhere, including an unrelated out-of-state investment that generated dividend and interest income. California's tax law let corporations deduct interest expense, but only to the extent that expense exceeded income received from such unrelated, out-of-state investments. Hunt-Wesson challenged this limitation as unconstitutional.
The question before the Court
Could California limit a multistate company's tax deduction for interest expense based on income the company earned from an unrelated out-of-state business?
Why it matters
Multistate and multinational companies filing state corporate income taxes gain a clearer limit on how far states can go in restricting deductions tied to unrelated out-of-state income. States that used similar all-or-nothing deduction offsets may need to adopt more proportional, ratio-based approaches like those used by the federal government and other states.
What changes now
The case is sent back to the California courts for further proceedings consistent with the ruling, meaning California cannot enforce its interest-deduction limitation as previously applied to Hunt-Wesson. This is a final decision on the constitutional question, though the exact tax refund or recalculation will be worked out on remand. Other states with similar all-or-nothing deduction limits may need to revisit their rules.
What this does not decide
The Court did not decide the separate dispute over exactly how much of Hunt-Wesson's interest expense the statute covers, since that dispute was irrelevant to the constitutional question and to the tax years at issue. It also left room for states to use proportional, ratio-based deduction allocation methods.
How the Court got there
The legal reasoning, step by step
- The Court applied the rule that a state may tax only a nondomiciliary corporation's 'unitary' income—income connected to its in-state business—and may not tax income from an unrelated 'discrete business enterprise' located elsewhere, absent some other connection to the state.
- The Court explained that even though California's rule was framed as limiting a deduction rather than directly taxing nonunitary income, a reduction in a deduction tied precisely to the amount of untaxable income functions the same as taxing that income directly, invoking the principle that 'a tax on sleeping measured by the number of pairs of shoes you have in your closet is a tax on shoes.'
- The Court considered California's defense that the rule was really just a reasonable way to allocate interest expense between taxable and untaxable income, since money is fungible and it can be hard to trace which borrowing supported which activity — a legitimate goal the Court had accepted in prior tax-arbitrage cases.
- The Court found California's approach unrealistic because it assumed that all borrowing supported the out-of-state investment first, regardless of whether the company invested any money in that activity that year, unlike the ratio-based methods used by the federal government and most other states that split borrowing proportionally between the two types of income.
- Concluding that California's rule did not reasonably allocate the deduction but instead swept in constitutionally protected out-of-state income, the Court held the provision an impermissible tax on income outside California's reach.
Doctrinal impact
Cases affected by this decision
Reaffirms Container Corp. of America v. Franchise Tax Bd. (463 U. S. 159)
Relied on for the standard requiring a rational relationship between taxed income and the taxing state.
Reaffirms Allied-Signal, Inc. v. Director, Div. of Taxation (504 U. S. 768)
Used to confirm that unrelated, nonunitary income cannot be taxed by a nondomiciliary state.
Distinguishes Denman v. Slayton (282 U. S. 514)
Cited as valid allocation of deductions but found California's rule went further than this precedent allowed.