Financial Institution Customer Protection Act of 2016

Financial Institution Customer Protection Act of 2015 Prohibits a federal banking agency from formally or informally suggesting, requesting, or ordering a depository institution to terminate either a specific customer account, or group of customer accounts, or otherwise restrict or discourage it from entering into or maintaining a banking relationship with a specific customer or group of customers, unless: (1) the agency has a material reason to do so, and (2) the reason is not based solely on reputation risk. Deems the "material reason" criterion satisfied if a federal banking agency believes that a specific customer or group of customers poses a threat to national security, including any belief that they are involved in terrorist financing. Prescribes notice requirements incumbent upon the federal banking agency to the depository institution regarding customer account restriction or termination, but states that the agency's notice to the customer is not required. Prohibits any notice to the customer if the federal banking agency requests or orders a depository institution to terminate a customer account (or a group of customer accounts) based upon a belief that customer or those customers pose a threat to national security. Amends the Financial Institutions Reform, Recovery, and Enforcement Act of 1989 to revise requirements for summoning witnesses and requiring production of books or other records the Attorney General deems relevant or material to a civil investigation in contemplation of a civil proceeding which may result in civil penalties for specified violations.