In its decision on the Ellingson case, the South Dakota Supreme Court noted that while Congress has the power to regulate commerce among the states, the states are permitted to act where Congress hasn’t acted.
The state Supreme Court had previously ruled that the Department of Revenue may impose the use tax on an out-of-state vendor’s services to South Dakota customers. For that decision, the court applied the four-part standard set by the U.S. Supreme Court’s 1977 decision in Complete Auto Transit, Inc. v. Brady. That is, a tax is not an unconstitutional burden on interstate commerce if:
The taxed activity is sufficiently connected to the state to justify the tax.
The tax is fairly related to benefits provided to the taxpayer.
The tax does not discriminate against interstate commerce.
The tax is fairly apportioned (i.e., it is both internally and externally consistent).
The state Supreme Court decision pointed out that Ellingson did not dispute the first or third points.
For the second point, it noted “Ellingson enjoyed the same benefits as any other person or business present in the state.” And having paid the use tax on its equipment that had otherwise not been subject to sales or use tax in another state, Ellingson was and “is free to bring the equipment back to work on jobs in South Dakota where Ellingson will continue to enjoy the privilege of conducting its business without being subject to additional use tax.” The court underscored that the use tax imposed by the Department of Revenue wasn’t limited to one day of use.
Finally, the state Supreme Court determined South Dakota’s application of the use tax in this case is both internally and externally consistent. Internal consistency means if every state were to impose an identical tax, there would be no multiple taxation. External consistency means when there is interstate activity, the state taxes only the portion of revenue that reasonably reflects the in-state activity.
Ellingson itself conceded the tax is internally consistent because South Dakota allows businesses to claim a credit for sales tax paid in another state, provided the state has a reciprocal agreement allowing South Dakota businesses to take a credit for sales tax paid to South Dakota. (Ellingson didn’t qualify for a South Dakota sales tax credit; it didn’t pay Minnesota sales tax on the equipment used in South Dakota because that equipment is exempt in Minnesota.)
Yet the company took issue with external consistency. It argued the tax is unreasonable because 90% of the company’s activities occurred outside of South Dakota during the audit period. Taxing the full (depreciated) value of the property, it argued, “fails to appropriately allocate the tax relative to Ellingson’s in-state activities.”
In a podcast about the case, Pomp called this a “blatant violation of external consistency.” Friedman agreed, saying “If there was ever a violation of external consistency, this is a poster child for it.”
Nonetheless, the South Dakota Supreme Court disagreed with Ellingson’s stance. “The activity at issue here is simply an in-state use of equipment that was purchased outside the state without ever having paid sales taxes on the property. This is reasonable, and when the use tax is viewed in the context of what it truly is — a substituted sales tax designed to preclude the loss of revenue by the State or local businesses that might otherwise result without the collection of such taxes — Ellingson’s argument is wide of the mark.”