In a lawsuit that could have taxing consequences nationwide, online retailers are suing South Dakota for trying to collect a sales tax from them. If the suit makes it to the U.S. Supreme Court -- as many believe it will -- governments would finally get an answer to their long-awaited question of whether they can collect a sales tax from online purchases.

South Dakota lawmakers essentially provoked the suit by passing a law they knew would be challenged by retailers. The law allows the state to collect a sales tax on Internet purchases from remote retailers who have a so-called “economic presence” in the state. Retailers had to start complying with the law by May 1. It challenges a 1992 Supreme Court case that ruled states can only tax retailers who have a physical presence there.

“[Lawmakers] were intent on getting this to the U.S. Supreme Court, and we are obliging that intent,” said Steve DelBianco, executive director of NetChoice, a trade association promoting e-commerce and one of the plaintiffs in the lawsuit against South Dakota.