Shia Labeouf Fight Video: Gets Beat Up?

I saw some pictures of Shia Labeouf today and his face looks like he was punched.
Then I read about his fight and even watched the video where you can see how he gets beat up by another guy with no shirt.
Shia LaBeouf emerged battered and bruised following the fight that took place outside a bar over the weekend in Vancouver.
What I don't understand is why was Shia Labeouf involved in the fight? Did he started it or was he attacked?
Is this something Shia Labeouf do? Because I heard this is not the first fight he's been involved in.

Shia LeBeouf exchanged words with another guy before security threw them both out of the bar. Once outside, the man reportedly removed his shirt and attacked him. You can see clearly how he gets beat up in the video.
The fight was broken up when a friend of Shia Labeouf came running between the two asking them to stop.
This isn't the first fight he's had, in February, police were called in to deal with a drunken fight involving Shia Labeouf outside a suburban California bar, Mad Bull’s Tavern.
He has also had two alcohol-related arrests: A DUI in 2007 and he was also charged with misdemeanor criminal trespassing after being intoxicated in a store in Chicago in the year 2008.