Probably the toughest category to call of the night. Feasibly any of them could win, though "If a Tree Falls" seems like the least likely of the quintent. The Weinstein Company's "Undefeated" is getting some very well timed buzz as the race nears its end, though "Pina," "Paradise Lost 3" and "Hell and Back Again" are all definitely possible spoilers.
Best documentary predictions below. Check out all predictions in all the categories here.
The Predicted Winner: Undefeatead
The Possible Spoilers:Pina, Hell and Back Again or Paradise Lost 3
Shoulda Been Here: The Interrupters, among many, many others