Npc Rule -- PvP & More
As most of you know, there is an NPC rule in place which is intended to prevent characters acting in a such a way that disregards the precense of NPCs. Complaints are made on occassion regarding this rules' violation or abuse. Either a player is disregarding the presence of an NPC(s), or a player is using the NPC rule to their advantage to avoid PvP. So what should you do if your character has intentions in proximity to NPCs? Notify a DM of your intentions. It doesn't necessarily have to be PvP. If you want your character to walk into a church with NPCs to perform vile acts, for example, be sure to only do so if you have conveyed your intentions to a DM, and that DM gives you the go-ahead to proceed.
The reasoning here ought to be obvious--a DM has the task of having the NPCs/the world react appropriately to your character's actions. In regards to PvP in proximity to NPCs, it is perhaps even more important to convey your intention to a DM and have a DM give you the thumbs up. So if you feel that someone is trying to hide behind the NPC-PvP rule, you are not without recourse.