The Marketplace Fairness Act recently introduced in the Senate would require online retailers to collect and pay sales taxes to states where they have no physical presence or democratic recourse. Overstock.com, eBay and the like could have to pay sales taxes to any state from which an Internet user placed an order, even if the company’s headquarters, warehouses and sales staff are located entirely in other states. …

The proposed law would hold online sellers to an entirely different standard. Websites would have to add taxes to a sale based on the shipping destination of the product, which may be a state in which neither the seller nor the buyer resides. We would never ask mom-and-pop store owners to do such a thing.

Politicians want this bill passed to raise new tax revenue for broken state governments facing budget shortfalls. But legislators in state capitals don’t want to make the hard decisions to cut spending or raise taxes on their constituents—they fear the voter backlash. So they’d like their allies in Washington to make it legal for them to tax people who can’t vote against them.