Washingtonians challenging their state’s new capital gains tax told the US Supreme Court on Monday that the ruling upholding the levy “opens a pandora’s box of dangerous practical implications on a national scale.”
“If Washington can tax out-of-state transactions based merely on the domicile of the transactor, then any state can tax its residents’ transactions anywhere and everywhere, regardless of the regime that governs where the transaction occurs or the property involved is held,” the challengers told the justices in their petition for review. Utah could tax alcohol its residents buy out of state, California could tax firearms its residents ...