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What is the Purpose of a Documentary: How They Work

A documentary film is a nonfiction film that shows real people and events in the form of a story. Documentaries have been around for a long time, but the advent of social media has created new and innovative forms of presentation. The question is: what is the purpose of a documentary and how does it serve to inform or persuade us? It’s not just an academic question for film studies undergrads, or a topic for a film festival seminar, but concerns us all as this article will show.

Truth Is Stranger Than Fiction

In many ways, the purpose of a documentary is in the minds of the filmmakers and in their actions when they make the film. The purpose of a documentary is determined to some degree by the individual filmmaker, their values, and the funding and support they receive.

The funding and support they receive are in turn determined by the prevailing standards in the industry.

The many documentary filmmakers I know personally are almost all motivated by good ethical and humanitarian impulses.

But that is, unfortunately, less true of many executives and producers in the industry. As is common with managers and executives everywhere, many are motivated by careerism rather than a commitment to public service.

This can and does seriously compromise the very purpose of some documentaries. Films are often shot against all odds, on very tight budgets, sometimes in very difficult locations, and are driven by the passion and determination of the filmmakers. Producers and executives, especially if the film is intended for television, are motivated by ratings and the perceived need for popularity.

This leads them to favor novel or unusual themes and quasi-sensational narratives. And to demand script after documentary script, as a way to control the editorial line.

However, the nature of a documentary is that it is about real events and real people, and this means that the story itself should be interesting enough to hold the viewer’s attention. The truth – when brought to the screen – is almost always stranger than fiction!

Related: How to Write a Documentary Script

The Public Service Ethos of Documentaries

The fact is that documentaries end up being a hodgepodge of interests, and the original intentions for a documentary can and will shift and change over time.

Documentaries are not made in isolation, and this is something to keep in mind when thinking about the purpose of a documentary and how it manifests itself on-screen.

In recent years, either “safe” documentaries that revel in beautifully shot but uncontroversial footage, or films that set themselves easy targets, such as “true crime stories” that avoid questioning serious interests, or any kind of political inquiry, let alone geopolitics, have become prevalent.

This is similar to the trend toward “cozy crime stories” in fiction, which offer readers the suspense of a crime without exposing them to the grim reality in which many serious crimes take place.

In turn, the old ethos of network public service has been lost and replaced by a much more corporate approach.

This is not to say that all documentaries are bad – far from it. But it is necessary to look more critically at their purpose and impact.

The Purpose Is Not Always Stated

The purpose of a good documentary film is sometimes explicit, but often not.

Sometimes you have to lie. You have to distort a thing to capture its true spirit.

Robert Flaherty

This is usually a conscious decision on the part of the filmmakers because part of the dramaturgical and suspenseful effect of a film is to allow the film’s agenda to unfold without making it too obvious in advance.

The Effect of Genre on Documentary Purpose

The purpose may depend on the different styles or genres of documentaries, as this may affect the scope and ambition of the goal of the film.

Documentaries are often divided into different “modes” or styles, depending on their characteristics. Although film theorist Bill Nichols suggested six – participatory, observational, representational, poetic, reflexive, and performative – I have added others below that are commonly encountered and can be characterized as different styles:


One of these categories is the expository documentary, which is a documentary that presents information, facts, archival material, theories, and ideas in a way that resembles classroom style.

In some ways, it is the ‘traditional documentary’ (although the very early documentaries such as Dziga Vertov’s Man With a Movie Camera, and Robert Flaherty’s Nanook of the North leaned much more heavily on esthetic cinematography.

A good example of an expository documentary would be Luc Jacquet’s film March of the Penguins (2005), which tells the story of the penguin migration to their breeding grounds. Or An Inconvenient Truth, presented by Al Gore and aimed at alerting the public to the dangers of climate change.

The purpose of such a film is to inform the audience or even to convince them of a certain argument. Very often in this type of film, there is a third-person narrator to provide context and perspective and fill in the gaps in the film’s narrative.

The narrator can also be used to introduce and conclude the film or to convey a certain point of view or theme in the film.

This type of documentary can evaluate the nature of the topic being portrayed, such as the arguments for and against a particular policy.

This type of documentary is often used to stimulate debate and discussion, based on documentary evidence. A genre known as “essay film.”

Related: What is an Expository Documentary


Contrast this with participatory documentary, where the documentary filmmaker acts more like an anthropologist and is not just an interviewer, but is involved in the narrative of the film.

The filmmaker is often a catalyst for change, as he or she intentionally seeks to change the world, to change people’s perceptions of the world, and to effect change.

A classic of the genre is Michael Moore’s 1989 film Roger and Me, which tells the story of the General Motors auto plants in Flint, Michigan.

The “hand of the artist” is very present in such a film.

The filmmaker’s voice can be heard, and he or she often appears in front of the camera, either in a cameo role or even in the front row to engage directly with the characters.

The point is to portray a particular point of view or experience, often from the perspective of a marginalized group of people.

The voices of those who are otherwise not heard are given a platform.

The goal is to capture an experience and document it in a raw and immediate way.


Observational documentary is often based on the belief that pure observation is closer to the so-called truth of a subject than a more objective film style.

Although objectivity is impossible to achieve in filmmaking, every single decision at every single stage of production affects the film and its documentary storytelling in a subjective way.

Observational documentaries contrast with participatory filmmaking because the observational filmmaker usually tries to remain invisible and unseen or to participate only slightly.

The hardcore of this type of filmmaking is known as direct cinema or cinema vérité.

A classic example of the observational documentary is Frederick Wiseman’s 1967 film Titicut Follies, which exposed the deplorable and inhumane conditions in a Massachusetts mental institution.

In common parlance, it has become known as the “fly-on-the-wall” film. This belies the fact that such films are often planned in advance. This style – especially in the sub-documentary genre known as ‘Reality TV’ – has come under criticism in recent years for being exploitative, as some films rely on finding raw and unguarded moments or scenes.

Very often in documentaries, observational approaches are mixed with explanatory approaches to get a film that works well.


Performative documentaries are films in which the filmmaker is highly involved in the film.

The way it works is to connect the broad story the film tells with the individual experiences of the presenter or filmmaker as he or she follows the subject through the film. In a performative documentary, a relationship is established between the filmmaker and the subject of the film.

The Morgan Spurlock film Supersize Me (2004) and Michael Moore’s Fahrenheit 9/11 (also 2004) are often cited as examples of this genre.

The drawback of this admittedly popular genre is that it posits universal truths based on individual perceptions, very often without attempting to support the arguments with actual evidence.

The central truth of such films is often the individual experience of the filmmaker, rather than something larger and more universal.

Re-Enactment and Docudrama

With some films, it can be very difficult to find the images with which to tell them. For example, films that tell stories from before the advent of the film archive, where an endless series of images can struggle to bring the subject to life. The solution may be to use docudrama or re-enactments of scenes from the documentary to draw the audience into the story.

This type of film can be very compelling if the actual events have been well researched. For example, discussions between high-ranking leaders that are usually top secret can be brought to the screen through documentary reenactment.

Such a reenactment can be quite experimental in nature. A famous example is a film The Issue Should Be Avoided, which tells the story of the murder of Polish army officers in World War II by the Soviet NKVD (secret police). The actors portray the different countries and their positions on this massacre.

A more recent docudrama for television is the miniseries Chernobyl (2019) starring actors Jared Harris and Emily Watson.


Many of the films I personally shot were investigative in nature. They dealt with serious geopolitical and human rights issues in the Middle East, Russia, the Balkans, and elsewhere. For example, ‘The Russian Newspaper Murders‘, ‘The Warning‘ and ‘Soldier‘ (Soldat).

These types of documentaries can be particularly challenging because not only do you have the journalistic challenge of figuring out where the truth lies, but it can also be very difficult to bring the story to life on screen through witness testimony.

Not to mention the challenges posed by the lack of footage with which to illustrate it.

Beware the ends of the earth and the exotic: the drama is on your doorstep wherever the slums; are, wherever there is malnutrition, wherever there is exploitation and cruelty.

John Grierson

The purpose of such investigative documentaries is also usually to expose wrongdoing, whether in the distant past or, more often, in the recent past.

There may be some overlap between observational and historical filmmaking and the research methods used in this genre.


Impressionist documentaries are much more about style, tone, and even the art of storytelling than factual explanation. You often find them in the form of a short documentary.

Although all films use juxtaposition as a central device to allow for movement, tension, conflict, and more, impressionistic, experimental, and poetic documentaries perhaps make even more use of juxtaposition to work well.

While undeniably cinematically beautiful, it is debatable whether such films can even be considered documentaries. Perhaps experimental cinema would be a better description.

The goal of such films is usually to appeal to the audience on an emotional level.


One of the consequences of the explosion of social media and countless channels everywhere is the rise of so-called reflexive documentaries.

This is where the filmmakers themselves are the focus of the film rather than an external story. It’s a kind of navel-gazing of filmmaking.

I suppose the purpose of such films is for the filmmakers’ internal experience to serve as a mirror to the story, rather than the film being a lens or window through which the story is observed.

Proponents of such a style would argue that it allows for a more direct relationship between the filmmaker and the audience because the filmmaker lifts the curtain on the filmmaking process.

There may be circumstances where such an approach to filming is the only option, such as in extremely dangerous situations where it would be impossible to take a camera on the road.

Ways in Which the Elements of a Documentary Can Serve Its Purpose

Most documentaries contain a number of elements that are part of filmmaking. The way these elements are handled by the filmmakers and the degree to which they are present in the films help determine the purpose and outcome of the films.


The building and breaking of tension and film by pitting one character against another or characters within the film against an external or sometimes internal antagonist. Conflict and tension are extremely important to the success of any film, not the least of which is documentary.

The challenge with the documentary is to not distort the purpose of the film while creating enough drama and tension to make the film actually work. Film structure is crucial in this regard, and as a viewer of a film, you may examine after watching how the structure serves the purpose of the film.


Exposition is the step-by-step unfolding of a film’s theme and hypothesis (central idea). It usually works through the interplay of interview clips, shared narration, and commentary to enrich and build a picture in the audience’s mind of what is happening.

Exposition is especially important when several storylines need to be tied together and direct testimony cannot cover everything in an efficient manner.


Documentary interviews are usually heavily edited to allow moments of insight or testimony to shine through and enable them to carry or support the story a film is telling.

The purpose of a documentary is not only conveyed on screen but also off-screen, where the relationships between filmmakers and subjects are crucial.

In recent years, interviews in documentaries have been denigrated as “talking head” material, to the point that some documentary filmmakers avoid them altogether. The truth is that the lack of magic in documentary statements and interviews is almost always due to a lack of research, sufficient curiosity, and commitment on the part of the filmmaker, or a lack of skillful editing.

Interviews, when they are just simply an exercise in hearing what you want to hear, are of no interest. And many, many, if not most interviews have that character. The interviewer who comes in with a list of bullet points they’re going to address one after the other. Interviews, properly considered, should be investigative. You should not know what you’re going to hear. You should be surprised.

Errol Morris

At the end of the day, ordinary documentaries are about reality and truth, and the best films touch on the human experience, which is inherently universal. Without human testimony, with the real person shining through, it is difficult to understand how such a goal can be fully achieved.

Mise en Scene

This is concerned with conveying mood and meaning through the placement of people, objects, lighting, etc. in a filmed scene. The choice of framing and point of view is critical for filmmakers to identify the purpose of the scene and how it relates to the overall plot. Internal decisions about staging can play a very influential role in how the end purpose of a documentary plays out.

Observation and Coverage

Ultimately, documentary filmmaking is about observation and coverage. Without sufficient placement of the camera and narration to allow the viewer to empathize with what they are seeing, to observe and feel that the moment in history is irrelevant and contributes to the overall purpose of the film, any film is doomed to fail.

The filmmaker’s choice of where to observe and how to observe a particular action is fundamental to the very purpose of the film.

How Documentaries Serve a Positive Purpose

Documentaries serve a valuable purpose in the world because they can be used as a check and balance of power to offer alternative and even divergent views of the world we live in. They can draw attention to ideas and social issues that would otherwise fall by the wayside.

They educate and inform, they entertain, and they can even excite and inspire.

Documentaries have the power to show how the world works – and often turn preconceived notions on their head in the process. Sometimes they can serve as an important historical document and factual record (as was the case with a film on which I worked as an assistant producer, A Cry From the Grave).

In this way, documentary filmmaking has a certain power and authority, and ultimately the purpose of the film lies not only with the filmmakers but also with the audience.

In the best documentaries, the story and the narrator are so good that they transcend the boundaries of the genre and take us to places we can not reach on our own.

Through story and testimony, a good documentary can explore, provoke, and challenge our perceptions and beliefs, and enlighten us in ways we can’t ourselves.

They convey human experiences of all kinds and link them to universal messages in a way that is unique in the arts.

This is the essence of strong narrative film and the documentary form.

In many ways, the best documentaries bring us face to face with our own souls and inspire us to become better people.

For this reason, it is a tragedy that documentaries have been so underfunded and received so little support in recent decades, while drama and fiction film has flourished.


Michael Renov – 50 Documentaries to See Before You Die