End Purchase of Firearms by Dangerous Individuals Act of 2019 This bill addresses reporting systems and mental health records for certain individuals who are prohibited from receiving or possessing a firearm. Specifically, the bill requires each state to establish a reporting system through which mental health professionals may report information about an individual committed to a mental institution who poses a danger or an individual who communicates a serious threat of violence, provide mental health records to the National Instant Criminal History Background Check System for use in determining whether a person is disqualified from possessing or receiving a firearm, and establish a process related to the temporary involuntary commitment of individuals at mental health facilities. Beginning 10 years after the bill's enactment, the Department of Justice must reduce by 5% funds under the Edward Byrne Memorial Justice Assistance Grant program for a state that fails to comply with these requirements. The bill expands the categories of persons barred from receiving or possessing a firearm to include persons who communicate a serious threat of violence to a mental health professional. Finally, the bill replaces various statutory references to persons adjudicated as a mental defective with references to persons adjudicated as ineligible due to disqualifying mental status .