In the nearly 75 years since the Oscars began awarding a documentary feature, no non-fiction filmmaker has ever been nominated for director, despite being eligible for the prize.

The most obvious reason is that “directing” seems antithetical to the spirit of nonfiction, which is about revealing unsullied truths about the world in which we live. Documentary directors have been generally regarded as observers or journalists, rather than as creative artists, and the Oscar process has, until recently, rewarded more conservative approaches to the form.

Such prominent documentary figures as Errol Morris and Werner Herzog worked for decades before the Academy honored them. Morris’ “The Fog of War” won the 2004 Oscar and Herzog’s “Encounters at the End of the World” was nominated in 2009. But even those films, as quirky and iconoclastic as they are, operated in the familiar spheres of journalistic interrogation and fact-filled nature docs. It’s always been expected that doc filmmakers give themselves over to the subject matter, rather than make bold artistic choices.

Yet the shortlist for the 2016 documentary Oscar continues a trend toward embracing non-fiction directors as auteurs, opening up the possibility of consideration alongside their fictional counterparts.

Among the potential nominees is Kirsten Johnson’s “Cameraperson,” a unique memoir composed of outtakes from Johnson’s career as a cinematographer; Ezra Edelman’s “O.J.: Made in America,” a kaleidoscopic 7½-hour look at American culture through the prism of O.J. Simpson’s rise and fall; Ava DuVernay’s “13th,” which draws a direct line between the amendment that ended slavery and the mass incarceration of black men; Keith Maitland’s “Tower,” an animated account of the 1966 mass shooting at the University of Texas; and Gianfranco Rosi’s “Fire at Sea,” the first documentary to ever win top prize at the Berlin Film Festival.

“If you look at the Oscar shortlist this year and compare it to the shortlist and nominations of 2002 or 2003, they’re just different,” says David Wilson, the co-founder and co-director of True/False Film Fest, which has been a reliable annual showcase for innovative nonfiction since 2003. “We’re seeing films that are artful, pushing boundaries, and taking real risks, and [committee members] are taking them seriously. That feels like progress to me.”

One of the breakout films from last year’s True/False Fest, Johnson’s “Cameraperson,” takes first-person documentary filmmaking to a startling new place. Over 15 years as a globetrotting nonfiction cinematographer, Johnson collected footage from locales as diverse as the war-torn regions of Bosnia and Darfur, a maternity ward in Nigeria, a secret prison in Yemen, and her childhood home in Wyoming, where her mother is suffering from Alzheimer’s disease. Without even the connective tissue of voiceover narration, Johnson creates a personal collage of her life and art that emphasizes the power of the camera to forge relationships and give a voice to the marginalized.

“I feel like one of the things I was willing to do as a director, was not know what this film should be, but to pursue, with the greatest intensity and attention, the deep questions that are completely real to me and urgent in this moment in history,” Johnson says.

She cites another film from this year’s shortlist, “Weiner,” about Anthony Weiner’s failed bid for New York City mayor, as an example of the dynamic qualities of nonfiction, which can change context and meaning both during and after filming.

“When you look at ‘Weiner,’ the meaning of Weiner allowing himself to be filmed in that moment changes over time. In my mind, the documentary relationship is always alive and changing. ‘Weiner’ means different things now than it did, as a film, when they made it, because historical events have shifted.”

The shifting of historical events also brings new meaning to “Tower,” an ingenious re-creation of the day Charles Whitman took the elevator to the top floor of the University of Texas Tower and opened fire for 96 minutes, killing 16 and wounding dozens more. In August 1966, the country had never experienced a mass shooting on campus, but they’ve become all-too-common in recent history, and Maitland’s powerful documentary celebrates the courage and humanity of those in the line of fire.

Working from a wealth of archival footage, as well as pictures he shot around campus, Maitland filmed much of the action in his backyard and composited it through the same rotoscoping animation technique that his fellow Austinite, Richard Linklater, used for “Waking Life” and “A Scanner Darkly.” Drawing on interviews with victims, witnesses, and other survivors, Maitland evokes the horror of that afternoon with a DIY resourcefulness that stands as one of the year’s shrewdest directorial achievements.

“I have a 40-foot palm tree in my back yard, and that became the stand-in for the Tower, for eye-line purposes,” recalls Maitland, who also synced the movements of his actors with the movement of background shots he picked up on his iPhone. “All along, the guiding principle was that the more immersive we can make the experience of the film, the more empathetic our audience will be with these characters.”

Maitland sees the boundaries between fiction and nonfiction filmmaking as fluid, citing the ensemble work of Robert Altman and Paul Thomas Anderson as influences along with doc directors like Brett Morgen (“Chicago 10”) and Ari Folman (“Waltz With Bashir”) who conducted similar experiments. “There’s been a blurring back and forth lately and I think that’s a good thing,” Maitland says. “The grammar and language of film is only about 100 years old, so it makes sense that it continues to be written.”

Compared to such singular documentary achievements as “Cameraperson” and “Tower,” “O.J.: Made in America” doesn’t exactly reinvent the form, but Edelman’s scrupulous assemblage of interviews and archival footage is radical in its own way. Edelman doesn’t even get to the murders of Nicole Brown Simpson and Ron Goldman in the first third of film, choosing instead to set the context of Simpson’s life and career within the larger scope of African-American history in Los Angeles. And the home stretch is a post-trial odyssey that few remember or witnessed, but says equally profound things about faded celebrity and black justice.

“For me, in terms of this film, the main undertaking [as director] was to take this massive idea and ground it in real narrative thrust and structure,” says Edelman. “As a storyteller, my job was to elicit the most honest, thoughtful, colorful responses from this vast array of interview subjects. I had to figure out a way to tell a story in as engaging and thoughtful a way as possible.”

Edelman credits the team responsible for the massive footage-gathering process, including producers Caroline Waterlow and Nina Krstic, but even with extensive archival images, he needed to fill in visual gaps, particularly in how he could suggest Los Angeles as a city of stark class and racial divisions.

“I thought, ‘We have to be able to capture this city from the air, and be able to show, literally, the two L.A.s.,’” he says. “[Viewers] had to understand the layout and the segregation that comes because of it.”

Though the Academy may not look to documentaries for director nods any time soon, the diversity of visions in this year’s shortlist suggest a continued openness to where a nonfiction film can go creatively.

For Wilson, what stands out about “Cameraperson,” “Tower,” and “O.J.: Made in America” from a filmmaking standpoint is the range. “You have three directors with three distinct visions, bringing a wholly different set of tools to the table,” says Wilson. “I think they’re three great films that illustrate the idea that nonfiction is not a genre. Nonfiction is a kind of storytelling, just like fiction is a kind of storytelling.

“If people can get their head around it, that will be the next big advance in how people think and talk about nonfiction.”