BETHUEL MONDLI ZUMA
You see you are talking about a person, people will differ.  I'll tell you that I know of a person who was pointing a firearm at his target and he shot right next to where he was standing.  Those things happen and ninety degrees is a very small angle, he can do that, a person can easily do that depending whether he's excited or he's shaken or he doesn't know how to handle the firearm properly so people do various things which you can't have a specific norm where you can apply to everyone as a general norm to say if you are carrying a firearm in this direction, definitely you must shoot in this angle.