Mass Shooter Database (The Violence Project)
Contains extensive details about public mass shootings in the US and their perpetrators, weapons, and victims, with a goal of “finding pathways to prevention.” The database, funded by a National Institute of Justice grant, covers 170+ shootings between 1966 and early 2020.
Examples of the variables include: the perpetrator’s employment status, known prejudices, and experience with mental illness; the victims’ relationship to the perpetrator and estimated years of life they lost; and the firearms’ make, model, and method of acquisition.