re: #17 Charles Johnson

Post priori classification based on searching existing databases, which may not have complete information. None of these were classified as “active shooters” at the time but based on later analysis, in some cases a decade after the facts.

In fact, they specifically note that the FBI does not classify incident as active shooting events. If there are more details in more recent shooting events, that will skew the sample quite easily, especially given the very small number of incident involved (160).