If a Michigan seller had already collected and remitted the sales tax, the purchaser is generally not liable for the use tax, as it would result in "double taxation". However, with this court decision, the purchaser will now have to "substantiate" the payment, either by the purchaser or the seller, of the sales tax. In Michigan, the obligation to pay sales tax rests with the seller, as it is a tax on the privilege of doing business. Under the statute, the seller may be reimbursed (not mandatory) for the amount of sales tax on the transaction. Substantiating that sales tax was in fact paid can either be with a receipt or invoice showing tax as part of the price paid, or an affidavit from the seller stating either the transaction includes sales tax or that the seller has submitted the tax to Treasury.
One concern resulting from this recent decision is the possibility of "double taxation" if both the seller and purchaser were to pay the tax on the same transaction. From the Court's view, there is "no double taxation" since the purchaser should be able to prove payment of the tax and be eligible for the exemption. For the purchaser to "prove payment" would mean retaining the proper documentation to substantiate the tax was paid on the transaction, creating a burden to the purchaser, but necessary in case of a use tax audit.