Director: Alex Gibney
Terry Kohut, Gary Smith, Chris Cooper, Ethan Hawke
Certificate: TBC

Silence can be a powerful thing. For the Catholic Church, it's expected, as a sign of a respect and a form of control. When Reverend Lawrence C. Murphy sexually abused boys in a Milwaukee home, the response was silence - both from the victims and the church. Alex Gibney's Mea Maxima Culpa breaks that silence. The result is a devastating and vital documentary.

Gibney brings to light the horrifying treatment of Terry, Gary and other boys in the 1960s. It was a decade later that the deaf men finally felt able to speak out, leaving leaflets in the local town exposing the priest in the first known protest against the church's behaviour. Nothing happened.

Their struggle to be heard is narrated by the men themselves, signed out while actors (including Chris Cooper and Ethan Hawke) lend their vocals. It's an incredibly effective technique, one that visibly communicates the human suffering at the hands of the church, while simultaneously empowering the victims to tell their story.

But while we might already feel familiar with the notion of child molestation in the church - that alone is sickening to consider - Mea Maxima Culpa packs its punch by revealing the personal fallout from the abuse, and then zooming out to show how widespread it actually is. South America. Africa. Ireland. All have similar tales of hidden abuse in the church, a string of predatory behaviour routinely concealed by authorities - all the way up to the Vatican.

Lawyers specialising in suits against the church and former priests contribute to the investigation, tracing a trail of cover-ups that lead directly to the former Cardinal Joseph Ratzinger (the until-recently Pope Benedict). But despite repeated attempts to uncover the maltreatment - Terry and Gary get support from Rembert Weakland, Archbishop of Milwaukee, only for him to be ordered to say nothing by higher powers - the church's concealment continues, paying off victims to maintain its respectable image.

Gibney tears into the hypocritical conspiracy with the righteous fury of Michael Moore in his prime. An occasional over-reliance on red-tinted reconstructions and ominous choral music takes some sincerity away from the piece, but the insidious horror of the subject matter is never lost. In many ways, this is a horror movie more than a documentary; a slow-burning, torturous film that shocks again and again.

Released in UK cinemas in the week of the Pope's resignation, it's hard not to link these revelations to his decision to step down. Gibney told Yahoo: "I can't help but think that the sex abuse crisis must have been on [Pope Benedict's] mind. There was no going forward on that issue while he was in office."

Of course, Ratzinger remains silent on the matter - it's no coincidence that no one from the Vatican agreed to be interviewed for the film. Silence can be a powerful thing, Gibney reminds us. A timely and provocative piece of filmmaking, Mea Maxima Culpa shouts the truth from the steeple tops. The quiet that follows is deafening.