How companies like Walmart and Target could get back billions in tariffs refunds

U.S. importers could be due more than $160 billion in tariff refunds after the U.S. Supreme Court ruled the White House’s emergency tariff authority was unconstitutional in February. Some of the biggest winners are American retailers who have faced billions of dollars of added costs from foreign imports over the past year. CNBC's Tobias Burns explains why there are still outstanding questions about how the refund process will work.