Exactly. raises some questions. Did the off-duty cops identify themselves as police officers? If not and they tried arresting him anyway, then Peterson did absolutely nothing wrong by resisting the arrest. Not only is it legal, but smart. Obviously I can't claim to know him, but seems to me he knows enough than to try and fight a police officer who showed his badge.
If some random dude tries slapping cuffs on me in a bar, you can bet your ass I'm not going to go willingly. No idea if the guy is a legit cop or not. Same as if you get pulled over by an unmarked car. Technically you are not obligated to submit to anything without them first proving they are police officers, at least that's how it works in Canada. Too easy to buy a used Crown Vic and play cop for a day. Same thing with off duty police.
As for the bar manager claiming Peterson was a trouble-customer all night.... it is also entirely possible that being in Texas he's a Cowboys fan. Cowboys fans don't always like Vikings players. He probably wouldn't mind seeing Peterson riding the pine for a few weeks.
Not saying he's not at fault at all, but have to wait and see what actually happens before crucifying or dismissing this.
also, saw this in a comment on nfl.com, but a valid point as well, being Texas and all:
Cops would not have jumped Gerhart, Kalil, Allen, Harrison Smith or Kevin Love. Am I white or am I wrong?