A documentary chronicling violent protests against the Vietnam war will open the 2007 Sundance film festival in Utah, organisers have announced.
Protestors clashed with Chicago police and the National Guard
Chicago 10 recounts the demonstrations surrounding 1968's Democratic National Convention, which saw protesters clash with the National Guard.
The film is directed by Brett Morgen, whose boxing documentary, On The Ropes, was nominated for an Oscar in 2000.
The Sundance festival was founded by Robert Redford in 1981.
It has a reputation for helping smaller, independent films break into the mainstream, and has showcased hits such as Maria Full of Grace, Napoleon Dynamite and Super Size Me.
Chicago 10 is the follow-up to Morgen's critically acclaimed documentary, The Kid Stays In The Picture, about legendary film producer Robert Evans.
Redford founded the Sundance festival in 1981
It uses archival footage, animation and music to tell the story of the 1968 Chicago protests, and the subsequent trial of eight activists.
The animated sequences feature the voices of actors such as Nick Nolte and Hank Azaria.
"I am thrilled and honoured," said Morgen about the film's selection.
"The festival's long-standing generosity and tenacious support of independent film-makers is exhilarating and humbling."
The 2007 Sundance festival opens on 18 January in Utah.