This bill requires the Department of Homeland Security to notify Congress within 72 hours whenever someone in DHS custody dies or suffers a serious injury, including injuries caused by DHS employees or contractors. The notification must include detailed information about the incident, including the circumstances, any use of force or weapons, whether medical help was provided, and what agencies were involved in responding. The bill also requires DHS to conduct internal investigations of all such incidents, with investigators coming from outside the chain of command of those involved, and to place any employee who used lethal force on administrative leave during the investigation. DHS must preserve video recordings for at least five years, obtain autopsy reports for deaths, and conduct mortality reviews to ensure treatment met departmental standards. The bill takes effect seven days after enactment and creates a reporting requirement to Congress within seven days of completing each investigation.