Microsoft is suing the U.S. Justice Department, claiming it exploits the company's trove of data on customers who use its cloud-based products. The Redmond-based company is asking the court to declare that a section of the law that governs electronic privacy is unconstitutional. Specifically, it wants to be able to tell customers when the government is investigating them. Under the Electronic Communications Privacy Act, the courts can order a company like Microsoft not to disclose when an agency