honestly idk

He did kill Torrig, but it was in a duel that he accepted. After Ulfric killed him, the Imperials named him a murderer and say he's guilty when actually he is innocent. Main reasons I join the Stormcloaks: Imperials are cheap, they try to kill me when I'm innocent, and you get better items and cooler titles.

good answer

You figure this out if you listen to Roggvir at his execution. I also got that backed up by talking to Torygg in Sovngarde.

Inocent

Ulfric is an inocent man! there is no denying that.

what makes you think that (not denying anything)

Well, Torygg did accept the duel, but a., Ulfric was older, stronger, and more experianced, and b., had the Thu'um on his side, which he wasn't supposed to use, since he wasn't Dragonborn. Also, I haven't talked to Torygg myself, but didn't he say that he would have listened to Ulfric?

Alungolah

...had the Thu'um on his side, which he wasn't supposed to use, since he wasn't Dragonborn.

Why? He had the skills to do it, so let the man do it! Which is more honorable, to be born with such power, or to acheive it through great effort? All is fair in a fight to the death (not really but sorta).

perhaps he was innocent but he wasnt exactly fair to other races who arent nord like he never let argonian in his city and look where the dark eleves live in a slum i joined the imperials to treat everyone fair 

hiith

Why? He had the skills to do it, so let the man do it! Which is more honorable, to be born with such power, or to acheive it through great effort? All is fair in a fight to the death (not really but sorta).

Because it has been stated before that the Thu'um is not to be used for combat by anyone besides the Dragonborn. The one Greybeard (can't remember his name right now, but he's the one you always talk to) comfirms this when he talks about killing or fighting or some  draaf like that when he says, "What is overlooked in the Dragonborn, is not permitted to any followers of the Way of The Voice." And yes, Ulfric is/was a follower of the Way of The Voice. His father gave him to the Greybeards as a child to learn the Thu'um, and become a Greybeard himself.

I think Ulfric is (almost) completely innocent. I usually join the Imperials though just because Ulfric makes me really annoyed. So I'm Pro-Stormcloak, Anti-Ulfric

Is he innocent? Or is he guilty? Nothing is ever so clear as black and white.

Ulfric did challenge the High King, and I believe he won fairly. A fight is a fight, and you use what is at your disposal.

Then came the problem with the Imperials. I don't know the full story, but it sounded like both sides were to eager to pick up swords.

Probably the tension caused by the Thalmor.

However, I personally do not stand my Ulfric's ideals, and as such, I join the Imperials every time, because I would not like the Skyrim that Ulfric would create.

Therefore, who is to say that he is innocent or guilty? It is not by me to judge. (Says the one who plays as a thief assassin who is totally guilty 0x0)