Microsoft is going head to head this week with the U.S. government in a case surrounding email privacy. Microsoft contends that users own their own emails even if they are stored in the cloud. The government says that emails become the business records of a cloud provider. The case, which is being heard in federal court in New York on Thursday, stems from a government demand to Microsoft this past December. The government demanded that Microsoft turn over customer emails as part of a narcotics investigation.