American documentary filmmaker Crystal Moselle's The Wolfpack tells the story of the Angulo brothers, who grew up in a New York housing project apartment which they rarely left for 15 years and then only under their father's dictatorial supervision.

One year they never went out at all. They were home schooled by their mum and not allowed to cut their hair.

Amidst this cult-like confinement they dispelled their boredom by re-enacting their favourite Tarantino and Batman movies, until eventually at the age of 15, one of the older boys decided to "break out".

His five brothers soon followed and the cover was blown on an extraordinary story. The resulting documentary won the Grand Jury Prize at this year's Sundance Festival and the Angulo brothers have since attained celebrity status.

The ethical questions surrounding The Wolfpack are various. Paul Byrnes in his review for the Sydney Morning Herald is primarily worried about issues of consent.

Most of the brothers were still minors when the first-time director began filming them and there is a seventh sibling, a disabled young woman. Their father is often drunk and appears to be delusional. There are hints of marital violence.

Other reviewers have raised questions about the legality of preventing children from leaving their home and the filmmaker's "exploitation" of the story.

However, my own concerns lie at the more subtle levels of documentary ethics, revealed in the story form and aesthetics of the film.

The truth is that whilst filmmakers can cite signed release forms to justify their actions, these are just pieces of paper. Consent in longitudinal documentary projects (which follow people over a long period of time) is an ongoing process.

It requires the development of a trusting relationship between filmmaker and participants to the point where the latter agree to be filmed. This mutual trust must then be reciprocally maintained throughout the production. You do something for me and I do something for you.

The Angulo boys' obsession with movies meant that once they decided to trust Moselle they were in.

It is impossible to predict the consequences of appearing in a doco. Just ask the filmmakers and participants in this year's Struggle Street (SBS 2015), which provoked controversy well beyond that deserved by a modest project with the corniest narration yet written by an SBS executive (no filmmaker would or could write such pap).

Apart from terrible music and a sensationalist trailer that provoked an outcry, its only mistake was to focus on the suburban underclass.

Australian filmmaker Dennis O'Rourke's Cunnamulla (2000) did the same in a country town, with similarly resulting hysteria from the middle-classes, who like to pretend that pregnant women never smoke bongs, especially on the toilet with their mothers next to them.

Generally with a documentary, you decide there's something worthwhile in participating and you trust the filmmaker so you take a punt, and in the case of the Angulo brothers it paid off. Unlike the residents of Mount Druitt, the film set them on the road to fame and possibly fortune: several of them now work in the entertainment industry.

For the other members of the Angulo family however, being sucked into this process was more difficult.

To her credit, their mother negotiated this terrain with skill and flair, liberating herself in the process and subsequently reuniting with her estranged family. But their father remains deluded and secluded. Moselle reports in an interview with Vice that he even likes to take credit for her documentary – in a kind of twisted justification for the virtual imprisonment of his children.

But then, what do you do when a pretty girl turns up to your house with a film crew having already won over the rest of the family? Chase them away, or grin and bear it?

You're wedged, as Tony Abbott would say, and the results are difficult to watch.

But the Wolfpack participants are adults (now, even if some weren't when filming started) and one assumes they can make their own choices, while the really vulnerable family member, the disabled daughter, is wisely left largely out of the frame.

Of course the terms of consent are negotiable to some degree and in order to gain that essential trust some filmmakers will at least offer participants a look at the rough cut or even an informal right of veto, but sshhh, don't tell the commissioning editor that.

So what are my concerns? There is an overall mood in The Wolfpack that is created not just by the story but by the way it is told, and I suspect this provokes the kind of ethical questions referred to above.

The director has said that it's a film about overcoming fear. My own feeling is of an overwhelming sense of oppression. Reviewers generally describe it as an uncomfortable but ultimately inspiring watch.

One of the reasons for this discomfort is the suspicion that more has gone on behind those closed doors than is being admitted. There's ambiguity around questions of responsibility.

For example, was the brothers' much loved mum complicit in her husband's view that it's the outside world which is the real jail, full of drug pushers, guns and muggers, not the harmonious world inside their jaded apartment? Was there physical as well as emotional abuse?

One might be tempted to accuse Moselle of not pushing for answers to these questions.

In this regard The Wolfpack is highly reminiscent of Capturing the Friedmans (2003), Andrew Jarecki's award-winning doco about a Jewish American family split asunder by accusations of paedophilia.

Jarecki openly declines to take a position on this, leaving us with an uncomfortable ambiguity. We want to know if it happened and who did it? We need resolution.

Like The Wolfpack, the film utilises home video footage, obsessively shot down the years by one of the Friedman sons.

Anna Broinowski's Australian doco Forbidden Lies (2007) is another of this ambivalent genre, which takes a more dramatised approach to the conundrum of whether Norma Khouri was really the witness of the honour killing of her close friend or had just made the whole thing up.

All of these films deal (or fail to deal) with the relationship between memory and truth, and sometimes home videos and truth.

But the reason why Moselle doesn't really go there is because, despite our frustration as an audience, it's not that necessary. It's sort of water under the bridge. Or it was when the filmmaker experienced it – because her lived discovery of the story was in complete reverse to the way the narrative plays out on the screen.

Moselle didn't meet the Angulo brothers until after their break out, when she saw them running down a Manhattan street in 2010, waist-length hair flowing and all dressed in black suits and sunglasses a la Reservoir Dogs, one of their favourite movies.

This piqued her curiosity and they began hanging out together in the park, discussing films and filmmaking. Eventually the boys invited Moselle back to their place.

She already knew they'd been home schooled and were a bit 'different', but here she discovered that she was the first friend they'd ever made.

By now she was filming them on an ad hoc basis, as they expanded their horizons for the first time with trips such as to the cinema and the beach at Coney Island. As an aside, how much Moselle engineered these events is unclear and another concern voiced by critic Paul Byrnes.

For example, in one scene in which they're filmed in a cinema, they appear to be the only people there - suggesting a less than spontaneous exercise arranged for the camera. But again I don't find this much of a problem. Filmmaking is a catalyst and we all indulge in a degree of engineering, even in the strictest of fly-on-the-wall approaches.

As Moselle spent more time with the brothers, the story of their confinement came out. While she soon got to know the mother, it was two years before she ventured a question to dad. By that time he had adjusted to the boys being out in the real world and any possibility of retribution was past.

It wasn't until some four years down the track that the boys told her: one year we never went out at all.

"The story of their childhood is still unraveling," she says in the interview with Vice.

Switch back to the movie. Here the story is told differently, in chronological order, as it happened, rather than how Moselle filmed it. Dramatically it wouldn't work any other way for an audience.

So we find out about the confinement first and then the break out, after which Moselle questions the parents (in short, mum's sorry but dad isn't and feels misunderstood).

Then we join the boys in their discoveries of the outside world. The film concludes with a moving trip by the entire family to an orchard – the brothers' first experience of the countryside.

What this chronological structure provokes in us is a very present discomfort at the boys confinement, which although told via interviews in the past tense, is presented in juxtaposition with old home videos and the boys' movie re-enactments that place us as an audience in the moment when the boys were confined.

We don't know that dad's rationalisation of his behaviour is being delivered several years after the breakout, when whatever hullabaloo there was has settled down and he's been more or less excommunicated in his own home. Instead we feel a very present danger.

This renders us as casualties of the overarching storytelling device chosen by the filmmakers. We can't be satisfied with the answers given and perhaps we feel that the filmmaker has opted out of the difficult questions.

As doco makers we all tamper with chronology for the sake of the narrative imperatives of story telling. If audiences know this then they trust us not to tamper with the integrity of the story in the process.

As the old editing adage goes, you can cheat but you mustn't lie. That is the contract.

Here the narrative drive is provided by Moselle's maxim given in another interview that "I wanted to see a transformation in my characters". This is of course a mantra of narrative filmmaking adopted by documentarians.

But the storytelling approach is not the only device colouring our view of The Wolfpack. The discomfort we feel is created as much by the aesthetic treatment of the film as by the adopted storytelling device.

The footage in the apartment is invariably dark and shadowy. The camera moves around a lot. And the use of mono-tonal music in a minor key on the soundtrack is disturbing, particularly when juxtaposed with home movie footage rendered in slow motion.

Seen separately for example, footage of a birthday party with the kids all with their faces painted in Kiss style might seem like a bit of weird fun, but overlaid with a tense and ominous soundtrack it becomes just that. Is this ethically wrong?

The filmmakers would doubtless argue that such sequences illustrate or reinforce the "truth" of the story, that to quote Moselle, "I always thought of the family as a kind of failed cult".

Other archive footage is similarly used to support this notion, such as the family moving around in a tight single-file circle, clad only in shorts, as if engaged in some kind of tribal shuffle.

What Moselle has said publicly is that after going through the mountain of video footage, most of which was mundane, "we found some stuff between the lines".

It's a truism that the closer a doco gets to a narrative the closer it gets to fiction.

The aesthetics of a documentary reveal the position and purpose of the filmmaker, especially when she/he is invisible in the film.

In The Wolfpack, there are no narrated explanations and Moselle is never seen, only heard occasionally asking a question. The use of atmospheric mono-tonal music is all the rage in docos these days, even behind interviews and dialogue.

And even the name "the wolfpack" is not the boys' own but a nickname coined by a friend of the director and now adopted by them for their own production company. Thus film and life are intricately intertwined – as they always have been for the Angulos. And the subject of documentary ethics is a similarly complicated affair.

This article was originally published on The Conversation.