Arguably the most powerful film presented at this year's Cannes Film Festival was screened with virtually no promotion and out of competition Thursday night. The film, The Central Park Five, by Ken Burns, America's leading documentary filmmaker ( The Civil War, Baseball, The War ) and his daughter Sara and son-in-law David McMahon, tells the story of the five teenagers who were arrested following the Central Park jogger attack in 1989 and how New York police and prosecutors employed manipulative interrogation to crack them, coerce their confessions, and send them to prison. Their convictions were overturned only after they had served their lengthy sentences, when the actual attacker, Matias Reyes, already serving time for multiple rapes, confessed and DNA evidence established his guilt. "I hope you will find this film unsettling," Burns told the audience before the screening. And there can be little doubt that it must have raised disturbing questions about America's criminal Justice system among the international audience in attendance. It is Burns's first feature-length documentary dealing with a contemporary controversy, and perhaps his most affecting -- especially as it shines a glaring spotlight on the often racial politics of American justice and the lynch mentality of some right-wing extremists that fuels it. Reviewer David Rooney concluded in the Hollywood Reporter "As a dense procedural, this is fascinating stuff; its miscarriage of justice stokes righteous anger and its account of lost youth and irreparably damaged lives is conveyed with moving solemnity." The film ends on a particularly rankling note. A decade after they were exonerated, it alleges, the five have received no apology -- indeed police and prosecutors continue to contend that they were guilty -- and no restitution.