No offense but saying the Deputy should have retreated down the stairs right away isn’t quite looking at the whole picture there. You can hear the man standing literally right behind the door and he says he has a gun. There was no telling how soon or quickly the suspect would be opening that door. The Deputy backed up and found the first thing of concealment being that 90 degree vertical wall on the right of the top landing of the stairs. Now if that Deputy were to have attempted to go down that stairs and that suspect opened that door right away, that suspect has the perfect vantage point right over the rail while you try and get down the stairs as quick as possible…which getting down or up stairs is never faster than being on flat ground. She’s now taking fire from right above her and most likely would have been a sitting duck and ended up being killed. If you asked anyone who has had enough training they will tell you that fighting in stairwells is a complete shit storm, it’s one of the worst situations to be in. Have you heard of the acronym “SHOCK”, it stands for Stairs, Hallways, Open Doors, Closed Doors, Known Area”. It goes from most likely going to be shit storm down to least likely to be a shit show (hopefully). If I’m about to get into a gun fight with someone I’m am not going to purposely choose to have it go down while I’m standing in the middle of a set of stairs.