So I was bored in Whiterun not to long ago. I decided I would go on a killing spree. I saved, and then my first kill was Nazeem. I cut his cocky head off, and got away with it because I was Thane ( ). Next was the old witch who was friends with Maven black Briar. I didn't get away with this one sadly, I started slaughtering guards left and right, and all of a sudden Vignar Gray-mane joined in, this was a big surprise. Next think I knew all the Companions were helping me kill off the town, even Earland joined in. So the gray-mane family, the Companions, and Lydia were helping me take over Whiterun. They even attacked children...

I just thought this was hilarious. I figure the companions would attack me since they are considered guards. I must be very popular.

I don't think they count as Guards, they stick up for you if their disposition is high enough (which is raised by being in a faction with them or performing quests for them.)

Well the UESP said they counted as guards, and may attack you even if they are your companions if your bounty is high enough.

Earlund is bawse. I done the same thing and i laughed my ass off when he started attacking the battle-born child lol

I dunno if the compainons are guards, but i know if you steal something from them you get a Companion bounty rather then whiterun bounty

well the UESP isn't the bible of skyrim, there's some errors in there too

I know this. It's a good place to look if you don't know something though, that's why it exists. Considering they also have keys to the gate of Whiterun It would make sense.