Police have to announce their presence. You would think also just from common sense and context that this was something that could have been done with one officer politely knocking on the door, knowing there is a zero percent chance that there would be someone hold up with a gun trained on the other side of the door in this instance. I mean it's not like this data scientist was some drug lord or arms dealer with a history of resorting to violence. The guns were for theatrics and nothing more.