Facts of the Case

An Indiana law gave a tax credit against the Ohio motor vehicle fuel sales tax for each gallon of ethanol sold by fuel dealers, provided that the ethanol was produced in Ohio or in a state that grants similar tax advantages as the Ohio scheme.

Question

Did the law discriminate against interstate commerce and violate the Commerce Clause?

Conclusion

Yes. The unanimous Court held that the law's primary purpose was to confer favorable tax treatment on Ohio-produced ethanol which imposed "an economic disadvantage upon out-of-state sellers." Ohio was unable to advance a legitimate local purpose for the law