and what becomes important is this next phase of the investigation where suddenly i need dozens of those people to start conducting interviews of victims and witnesses, to understand what truly went on, to start thinking about victimology. why this particular office, why these particular victims who did it start with, what was said, the details of what was worn, rounds that might have been expended, the description of the weapons. so the complexity of the investigation changes very dramatically from s.w.a.t., tactical, gunfight to logical investigation so i understood what happened. >> tom fuentes, it is very rare, statistically speaking, for a mass shooting to have been conducted in this country by more than one person. the idea that it was three people potentially based on the information we're being given by law enforcement is not a normal circumstance when it comes to mass shootings in this country, sad enough as it is to say that there is a normal circumstance