if weapon is out for too long, random NPCs will sometimes turn hostile

[TheBlob2]

a mod that makes it so if the player has a weapon out, and they have had that weapon out for like 10 seconds or so, random NPCs who also have weapons will turn hostile and attack you

[flamenx01]

This mod might have something similar to what you are looking for. I'm sure if you aim at people they turn hostile.
http://www.nexusmods.com/newvegas/mods/40593/?

Edited April 20, 2015 by flamenx01