On September 20, Puerto Rico was devastated by the strongest hurricane that has hit the island in the last century. In the weeks after the storm, the government insisted there were only a few dozen deaths, but reporting on the ground by the Center for Investigative Journalism suggested there were hundreds. Officials also refused to provide overall mortality statistics that could help measure the impact of the storm. Given the lack of a reliable official death toll, we put together our own database with information collected from family members through an online survey, reporting, and tips. We verified those deaths by matching the victims' names with government death records CPI eventually obtained through a lawsuit, and through nearly 300 phone interviews with victims' relatives. We analyzed that material, as well as historic demographic data, to detect changes in mortality trends after the storm.