Threat Information Protocol for Sharing Act of 2019 This bill establishes several new reporting requirements related to information received by the Federal Bureau of Investigation (FBI) through the national tip line relating to an individual or threat. Specifically, the FBI must submit the following: monthly reports to state law enforcement agencies and fusion centers on all information received by the national tip line relating to an individual or threat in the state during the preceding month, annual reports to Congress on total reports received by the tip line and the total number submitted to state law enforcement agencies and fusion centers, and annual reports to Congress on criminal events involving an individual or threat that had been the subject of a report received through the tip line prior to the criminal event. Additionally, the Government Accountability Office must review and report on the operating processes and procedures of the tip line.