Normally, a documentary is supposed to be a movie or TV show about something true: it "documents" something that really happened. Not all documentaries actually succeed in portraying the truth, however. People make mistakes, and some documentary makers are trying to promote their point of view and, understandably, choose to gloss over things they don't consider important. Usually, a documentary filmmaker is expected to adhere to reasonable standards of journalistic integrity and remember to do the research.
Sometimes, though, a documentary filmmaker just doesn't care, and any attempt at accuracy or finding the truth goes out the window, but the result is still presented as non-fiction, oftentimes with quote-mining and Manipulative Editing. When this happens, you usually end up with a Documentary of Lies. For a succinct demonstration of just how truth is commonly manipulated check out Luke's Change: An Inside Job a satirical take on Star Wars in the style of Loose Change that uses pretty much every common technique found in this trope.
This is not a Mockumentary, which is explicitly a fictional scripted movie (usually comedy or horror) done in the style of a documentary. In order to be guilty of being a Documentary of Lies, a documentary has to claim that something is actually true when any reasonable investigation would show otherwise. The filmmakers were either negligent, outright liars, or just plain crazy. Don't Shoot the Message becomes a common result.
Television networks that produce a Documentary of Lies usually justify it by saying — off camera — that the programs are entertainment only and the filmmakers have no more of a duty to reflect the truth than do the makers of The X-Files; if viewers mistake it for non-fiction, that's their problem. That defense might work if the programs themselves were actually presented as fiction...
Frequent topics of this sort of program include psychics, UFOs and alien abductions, conspiracy theories, claims that history as we know it was Written by the Winners, ghosts and other supernatural entities, and objects with alleged religious significance.
Not to be confused with the Documentary Episode, the Faux Documentary, the Mockumentary, or the Faux-To Guide. See also Twisting the Words, which is this trope applied to subjects who were telling the truth in the first place. If the news takes it utterly seriously, Media Scaremongering. Falsely Advertised Accuracy is the related phenomenon for a work of literature that claims to be based on facts and research but is in fact a near-complete work of fiction.
See also Based on a Great Big Lie. Lurid Tales of Doom is this trope applied to newspapers and news broadcasts.
In-Universe Examples Only:
- The mockumentary The Dark Side of the Moon, made by French TV Channel Arte in 2002, is a grand spoof of these kind of works, right down to its crazily Troperiffic portrayal of a generic Apollo Moon Hoax. The movie is meant as a funny tribute to the late, great Stanley Kubrick — who appears in the movie as a key participant of the conspiracy, filming fake Moon walks. There are innumerable Lampshade Hangings and deliberately nonsensical or silly bits thrown in, yet the tone is constantly deadpan. The Twist Ending reveals the real nature of the movie. Pity that many conspiracy theorists still took it absolutely seriously...
- Spanish TV broadcaster La Sexta developed a similar idea, based on the February 23rd 1981 coup d'etat. It puts Pedro Almodóvar as the supposed director of the coup, which would have been conceived to secure democracy in Spain and increase the King's popularity.
- Maddox of The Best Page in the Universe fame created the YouTube vid Unfastened Coins: The Titanic Conspiracy, which parodies this trope and the 9-11 conspiracy film Loose Change for all it's worth (including parodies of "undeniable verification tests" done with a model of the Titanic in the author's bathtub).
- CollegeHumor did a parody of conspiracy theory documentaries with their video "Deceptive Deceptions". This "truthumentary" uncovers the gargantuan Conspiracy Kitchen Sink that has controlled humanity since the dawn of time through an absurdly long stream of Insane Troll Logic.
Narrator: Did the Vatican suppress the fact that Jesus and Mary Magdalene together had... a dog? Was Princess Diana really killed in the Challenger space shuttle disaster? Was the Loch Ness monster actually a descendent of Jesus' magic dog? Did the Twin Towers ever really exist? The clues are everywhere if one chooses to make stabs in the darkness.
- Luke's Change, a parody of the 9/11 conspiracy documentary Loose Change, presents a compelling case that the destruction of the first Death Star was an inside job set up by the Skywalker family. This was made before Rogue One, which involved someone sabotaging the project from within.
- Fellowship 9/11, a parody of Michael Moore's Fahrenheit 9/11 via The Lord of the Rings. Did you know that the Battle of Helms Deep was a false flag operation to allow the Fellowship Group to invade peaceful, oil-rich Mordor? Michael Moore and Senator Grima Wormtongue (D, Rohan) explain it all.
- Kimba the White Lion has an in-universe example where a Prima Donna Director who's making a nature documentary in Africa put a captive orangutan in his film even though there are no orangutans in Africa. When he's called out on this he says that because he has an orangutan in Africa, he can say that there are orangutans in Africa.
- The Last Broadcast. Almost the whole movie is this, but only in The Reveal do we get to know that the In-Universe documentary we've just been watching actually contradicts what had really happened. The director/narrator himself, David Leigh, is the murderer in the case he's been investigating, and he seeks to exonerate Jim Suerd due to his ego being unable to take the fact that his 'perfect crime' was being attributed to some random psycho. It's also insinuated that all documentaries are like this, subject to the biases of the people making them.
- The Life Aquatic with Steve Zissou and Alien Autopsy both have main characters that re-enact their exploits for cameras and then pass off the footage as legitimately fly-on-the-wall.
- The remake of Beyond a Reasonable Doubt features CJ, a reporter who became a star with his acclaimed documentary on a homeless woman who died a drug addict. For a follow-up, CJ decides to take down a corrupt D.A. by having himself framed for murder and show the D.A. will ignore evidence of his innocence. However, in a classic case of Gone Horribly Right, the frame-up is too good and the friend who has the evidence to clear CJ is killed on his way to the courthouse so he is found guilty. His girlfriend, Ella, manages to prove his innocence and the D.A.'s corruption. However, going over the evidence later, Ella realizes the truth: the woman whose murder CJ framed himself for has the same tattoos as the homeless woman from his documentary. Ella realizes this means they were one and the same and CJ's entire "report" was a massive fraud. The prostitute was blackmailing him with the truth so he killed her as part of his plot. CJ begs Ella to listen to him but she's already called the police to take him in.
- In Sharp Ends, set in the First Law universe, we get "Freedom," a shamelessly romanticized depiction of Nicomo Cosca, infamous soldier of fortune, written by hack author Spillion Sworbreck. The drunken opportunist with a Chronic Backstabbing Disorder Cosca and his Army of Thieves and Whores are depicted as cartoonishly principled and heroic as they "liberate" a town, when the reader knows the real story must have been quite different. In the end, Sworbreck's editor has written a note demanding rewrites to make the story even more fanciful.
- Babylon 5 had an example in the fourth season episode, appropriately named "The Illusion of Truth". Earth had fallen under control of a malevolent dictatorship, which controls the Inter Stellar News Network. The title station had broken free of Earth Control in protest of the President abusing his executive powers and bombing civilian targets on Mars. A group of reporters from the Inter Stellar News Network come to get the station's personal side of the story back home. They Lied. Every line and image was twisted and distorted to make the heroes, namely Captain John Sheridan, look like villains who bow down to alien pressure and commit human experimentation. The director responsible had earlier told Sheridan, however, that he always tried to tell as much of the truth as he could without getting in trouble. The near-total lack of truth in the final product is, in this interpretation, a dire warning to those on Babylon 5 watching the broadcast.
- In UnREAL (2015) Coleman is introduced in season 2 as an award-winning documentary filmmaker who's hired as the new producer of Everlasting. He spends much of his time railing on how horrible and manipulative reality TV is and ends up wanting to destroy the series totally. Rachel fights against him and works with Quinn to force Coleman out. When Coleman threatens to use information about the show's dark methods, Rachel counters by revealing what Coleman's ex-girlfriend had told her: Coleman had hired downtrodden extras to pose as "the sex slaves" in his "documentary," meaning Coleman is as much a fake as Quinn and Rachel are.
- Played for laughs on House as House is followed by a documentary crew for a day. He naturally insults them for being horrible and presenting false stories and gives them the treatment of him berating his staff and patients alike, caring less for a sick kid and more solving the mystery of his disease and showcasing what a terrible person House is. When the documentary is shown, House is outraged (and Cuddy moved to laughter) to see that the filmmakers have fixed it so House is shown as a kind-hearted man who truly cares for all his patients, treats his staff with the utmost respect and appears to admit to being moved to become a doctor by the movie Patch Adams.
- This becomes one of the major reasons for the Abstergo Project created by the Templars in the Assassin's Creed franchise. By Assassin's Creed IV: Black Flag, Abstergo successfully creates an industry where they use employees to uncover real history and twist the information they find to make historical, evil Templars look like heroes and the historical, heroic Assassins look like villains. Then they put the information out as movies, video games, television shows, and documentaries, claiming the consumer is experiencing real history.
- In the "Lair of the Shadow Broker" DLC for Mass Effect 2, you can find in the Broker's information terminal purchase records from Admiral/Councilor Anderson, showing that he bought a documentary which portrays Saren Arterius, the primary antagonist of Mass Effect, as being a misunderstood hero... alongside a copious amount of alcohol.
- Gerry Romero is working on one in Mega Man Star Force 2. He fakes a string of monster sightings using a submarine... then eventually becomes the monster thanks to EM Wave Changing and goes completely insane.
- In the Strong Bad Email "bedtime story", The Cheat is terrified by a "shock-u-mentary" that claims gingivitis makes your gums look (and taste) like chocolate pudding, forcing Strong Bad to cook up an elaborate bedtime routine to help The Cheat get to sleep.
- The Simpsons: In "Homer Badman", Homer is accused of inappropriately groping a young female babysitter, when in fact he was just pulling a gummy Venus de Milo off her bum (she had sat on it). He gives an interview to Rock Bottom (an expy of the '90s tabloid news program Hard Copy), which they then air heavily edited to make it seem as though Homer admits guilt and then attacks the journalist in question (who is clearly outside while Homer is inside). It ends with the disclaimer "Dramatization! May not have happened." At the end they issue a retraction, along with a comically long list of things they lied about besides this.