From misplaced questions to accidental transcription errors, interview fumbles are obviously to be avoided under any circumstances, but you particularly want to be on your game when the subject is one of America's preeminent documentarians – someone whose own profession is built on a level of journalistic expertise. So you can imagine my mortification when my iPhone recently took it upon itself to wipe its own memory clean – deleting, among other things, all aural evidence of my face-to-face conversation with Alex Gibney at last month's London Film Festival. 

The prolific filmmaker, an Oscar-winner in 2007 for his devastating legalized-torture study “Taxi to the Dark Side,” was in town for the European premiere of his superb new filmMea Maxima Culpa: Silence in the House of God,” which would win him the festival's Best Documentary award the very next day. The film, which hits US theaters today, is not the first to examine the horrific history of sexual abuse within the Catholic Church, but it is arguably the most penetrating, methodically tracing a dense network of crime and cover-up all the way from Milwaukee to the Vatican itself. It could well earn Gibney a deserved third Oscar nod. 

Speaking over the phone from his New York office earlier this week, Gibney casually waves off my apologies for having to restage the interview. “Trust me, I've been there,” he says with a light laugh, his crisp, deliberate voice sounding rather less exhausted than it did in the bar of London's Mayfair Hotel a month ago. It's hard to imagine interviews – or any information, for that matter – slipping through the director's fingers, so keen and diligent is his filmmaking style across a broad range of subjects, from the fall of Enron to the fizz of Hunter S. Thompson. “Mea Maxima Culpa” is among his most perspicacious works: weaving a profoundly moving story of human heroism through a tough-minded analysis of a global scandal, he carves out new angles in a story he admits initially fearing had already been adequately exposed. 

“I was of two minds about it, to be honest,” he says, remembering when producer Todd Wider came to him with New York Times journalist Laurie Goodstein's story about Father Lawrence Murphy, a priest revealed to have molested hundreds of boys at a school for the deaf in Milwaukee, and the four victims who labored for decades, in the face of clerical and governmental indifference, to bring Murphy to justice. “On the one hand, I felt an awful lot had already been done on the subject. At the same time, I'd been raised Catholic and thought that if there was something new I could contribute, I should do it.” 

Digging further into Goodstein's story, Gibney found himself intrigued by the documented connection between crimes in Wisconsin and the Vatican, and the challenges of playing an intimate human tale against a larger international exposé. “It was a good opportunity to get a greater understanding of the Vatican's role in the cover-up,” he explains. “And the third reason I decided to do it, though it took a little longer to understand, was the heroism of the survivors themselves – these four deaf men. In the midst of this very dark story, there was something there to celebrate.” 

Introducing the film at its first London screening, Gibney quipped, “I was raised Catholic, and this is the result.” He may have delivered the line flippantly, but the director insists that his Catholic upbringing – though he now regards himself as lapsed – had a significant bearing on the film. 

“It might kill you to say it, because the film really takes on the Catholic Church, but I do think there is a sort of affection for certain rituals, and an authenticity to the presentation of those rituals, in 'Mea Maxima Culpa',” he says. “It's a kind of shorthand for the emotional identification that Catholics inevitably have with their church. I think the Catholic Church is quite consciously extreme in some ways, because that identifies its followers with a very peculiar kind of tradition. There's not a lot of difference between a lot of forms of Protestantism, but if you're a Roman Catholic – particularly of my generation, raised at a time when you could still go to the Latin Mass – there's an intense emotional connection with that, even if you're not still devout.” 

“It's not 'Religulous',” he remarked on our first encounter in London, referring to Bill Maher's unsupportably snide anti-religion tract released in 2008. “It's not even about religion per se; it's about the abuse of power, the abuse of faith. And I think it would be quite easy for other filmmakers, who weren't raised with the religion, to be more mocking of the liturgy itself, and less understanding of the way that liturgy actually insinuates itself into your character.” 

As if to demonstrate that such horrors are hardly limited to the Church, the sexual abuse scandal currently rocking the BBC in the UK offers some timely parallels with the situation explored in Gibney's film. “It's disturbing, but at the same time kind of gratifying to see these stories breaking open. I think for a long time they were held in check, and the silence was the thing that was most pernicious. Victims were afraid to come forward, often against people who had these immense reputations – something you also see in the Lance Armstrong story. They were discredited. So you see how the reputations of powerful institutions act to silence people.” 

“My film may be about the Catholic Church, but you can see this same abuse of power, in other institutions, whether it's Penn State or the BBC. And you see how predators can live in plain sight due to their outsized reputations – how Jimmy Savile got away with it is the same as how Father Murphy got away with it. So I think 'Mea Maxima Culpa' has a lot to say about how the mechanism of cover-up works, when institutions are more concerned with protecting power than protecting lives.” 

Though the making of the film saw Gibney taking on some daunting institutions – a terse intertitle mentions that no Vatican representative was unwilling to be interviewed, though the director tells me he pressed hard for one – the smaller story of the deaf men, whose attempted action against their abuser began with handmade protest flyers at school before ascending, in decades to come, to higher legal authorities, was no less challenging. 

“Initially I was terrified of telling this story in audio-visual terms, because all my key witnesses were deaf, and I'd never really penetrated that world before,” Gibney say, “but I think it ended up being one of the film's most cinematic aspects.” He explains the unusual shooting setup devised for the interviews with the four subjects – Terry Kohut, Gary Smith, Pat Kuehn and Arthur Budzinski – which involved four cameras in a studio, while Gibney conducted the interviews from a separate room, with a translator. 

“By having me in a separate room, which I would otherwise never have done, we were able to mike them,” he explains. “And at first they thought we were absolutely crazy: 'Why are you miking us? We don't speak!' But it was the sound of their struggle to communicate, at least to the hearing world, that I found so moving. So in terms of cinema, photographing and recording the deaf became a defining element of the film.” 

Voicing the deaf was another priority. After deliberating back and forth with an executive producer who felt subtitling the deaf men's dialogue would be the better route, Gibney decided instead to have their testimonies narrated by actors – including such well-known names as John Slattery, Chris Cooper and Ethan Hawke. “I wanted the hearing viewers to focus intently on their signing, on their actions, rather than reading subtitles,” he says. “Their language is very expressive. I also thought it would be more emotional to do it with actors who can inhabit these characters: as a hearing viewer, you feel it more with a voice attached.” 

The casting process was intuitive, based on finding voices that matched the physical presence and manner of the men themselves – while Slattery, also raised Catholic, had his own emotional connection to the story. Gibney chose to shoot the subjects much as you would shoot actors: “We were originally advised that you can only shoot deaf people in a wide frame so you can see every aspect of their gestures. But I missed the power of seeing their eyes, their mouths, their hands up close. So rightly or wrongly, I went against that advice.” 

Arousing more dissent than Gibney's portrayal of his deaf subjects has been the film's stylized reconstructions of their traumatic childhood experiences. Menacing but not explicit, these shots of red-lit corridors and encroaching footsteps have been questioned by otherwise admiring critics for an aesthetic that the director freely admits is inspired by Hammer Horror films. Such imagery, Gibney says, is fully in keeping with his subjects' own experience. 

“With each film, you find a logic and a style that makes sense for that particular story,” he says. “In some films, dramatizations make no sense at all. In this one, I felt strongly that they did, because there's a sense of almost collective memory that some of the kids had, and also a sense of ritual – both of which I felt the dramatizations respected. They all remembered the red glow of the exit sign, they all remembered being terrified in their beds because they couldn't hear Murphy coming, and then suddenly seeing his feet. These details resonated very strongly with me, and I decided it was important to visualize them, so there wouldn't be just an intellectual engagement with their memory.” 

Gibney also employed aestheticized reconstructions of Church rituals for effect. “There was a peculiar kind of communication going on that I felt was important to describe: the violation of the confessional. There are people who call that 'soul murder.' You're so exposed when you're confessing something to a priest – what could be worse than the priest abusing that trust to prey on you? The Church regards that as a crime in canon law, which has no statute of limitations. So to be able to film that as a ritual was terribly important to me.” 

“We actually found a church in Rome, of all places, which had a very peculiar setup with glass on the doors – so you could see the shadows of people inside the confession booth without being able to actually see who they were. That was powerful to me, so we duplicated that effect in a studio. And we also had a rig whereby we shot down vertically from above, almost as if from the perspective of heaven, on the confessional. That perspective had a kind of evidentiary quality to it, a crime film quality, that I also rather liked.” 

In addition to the still-controversial area of dramatization, Gibney is open to other modes of experimentation with the documentary form, and describes rigorous purists as “a bit of a bugbear.” “Critics can say what they like about the films, but very often, there's a certain expectation of documentaries that they're supposed to be like PowerPoint presentations,” he says. “I see documentaries as movies. So when I see some critics writing that we could have done without the recreations altogether – well, perhaps. But in this case, I think not: I think the audience gets an emotional power from them that the survivors themselves have recognized. But then, I recently did a film about a hockey player – a tough guy, an enforcer – and used no narration and no recreations. It all depends on what that story seems to demand.” 

Gibney professes to be delighted by the growing number of recent films that are bending the so-called rules, blurring the line between documentary and drama in provocative but productive ways. From this year, he cites Bart Layton's acclaimed debut “The Imposter” – “It plays like a feature, mingling real characters with actors, saying each other's words in ways that are very powerful” – and Sarah Polley's upcoming family memoir “Stories We Tell” as exciting examples of where the form can go. We spend a good few minutes jointly gushing about the latter film, which cleverly plays on our perception of Super-8 home movies to uncover surprising truths. 

“Polley's not tricking the audience, she's letting them in on the device in a way that I think is very important,” he says. “Who says documentary has to be a certain way? Who wrote that rulebook? I'd like to find them and kill them. Many people have this memory of traditional TV documentary-making that aims to portray pure reality, and I just don't see that as the only option. And I think it's fantastic that more films are resisting that idea now.” 

As an active member of the Academy's documentary branch, Gibney hopes to see voters – many of whom are, at this point, wary of more radical creative innovations in the field – embracing a wider range of achievements. He's as interested as the rest of us to see if this year's overhaul of the voting system, which includes dissolving the voting committees and revising eligibility criteria with an emphasis on public theatrical releases, has a discernible effect on a category that has repeatedly bypassed works of great artistry and significance. 

“There's a wide range of views in that branch of the Academy about what makes up a documentary and what doesn't,” he says. “My view is quite fluid; others feel strongly that one should observe a more rigid definition. So we'll see. I think the changes were intended to eliminate a certain kind of abuse, and they've caused other problems. But we should let the rules roll this year and see where we get in the end, and then review them.” 

Though he acknowledges that “you can game almost any system,” Gibney is pleased to see the back of the committee system, by which films were voted onto the shortlist by an assigned smaller group of voters within the branch. “If you were a member of a committee and a film came before you that was made someone you dislike – or you had a certain distaste for it because it didn't fit your perception of a documentary – you could kill that film just by giving it a very bad score. And that was a shame, because it shut out a lot of very deserving films: 'Senna' was one, Steve James's 'The Interrupters' was another. They didn't get their shot with other voters, which was wrong.” 

He admits, however, that the alternative system does demand that voters watch an unrealistic amount of films. Even as a dedicated voter, he doubts he'll get through the box of 70 screeners he's been sent to consider. With projects about Fela Kuti and Lance Armstrong already in post-production – he tells me he likes to hop between lighter and weightier subjects – it's easy to see why he doesn't have much spare time on his hands. One hopes, however, that “Mea Maxima Culpa” catches the attention of his fellow voters.