UPDATE 1-U.S. top court grapples with validity of credit card surcharge law
January 10, 2017 at 15:08 PM EST
WASHINGTON, Jan 10 (Reuters) - The U.S. Supreme Court on Tuesday struggled over how to decide a challenge to a state law barring retailers from charging more to buy with credit instead of cash, debating whether it merely regulates prices or violates merchants' constitutional rights.