Attacking without reason is one of the operational guidelines that i proposed to the leaders of DW.
Basically it states that we will only initiate combat against a pirate that has either a bounty or is on our KOS listing. The KOS listing will be a precise list of those pirates that attack BH without cause or notification (i.e. the pvpwhores). Reasoning for this is simple, you attack a BH, expect them to return the favor in spades.
You dont want to be attacked, dont give us a reason.
There are also 4 other guidelines that are up for a vote that will change quite a bit of how we operate and here is the kicker, every one is well within the stated RP of the bounty hunters guild.
EDIT -
as far as a ship line, BH and civilian just as everyone else. Usually flying anything else will get you shot by that faction. Which btw, I will also agree that any merc flying a BH vessel be either sanctioned or blasted out of the sky for theft. Same as any other faction would do and does.