Documentaries are built around and through the opinions of their makers. Citing them as viable resources to make a point only really proves whatever point the producers, directors, and editors want you to believe. For example, the show Making a Murderer on Netflix is roughly 10 hours long. It's stated in the documentary that the creators of the show shot around 200 hours of film.
The illustration to the right is harshly cynical, painting all of media as "spoon-feeding" their audience. While it's attention grabbing and vitriolic in nature, it's meant to play as satire and wholly oversimplifies how media as a general entity affects us. There's an awareness within Making A Murderer's dialogue that "fairness" and "telling both sides" is key, and that the show is structured around playing the middle ground. But, by the end of the roughly ten-hour-long season, it's quite clear there are hidden biases from within the information, chosen to construct the doc as how the filmmakers believed Steven Avery to be innocent.
And, much of the information presented to audiences about the police themselves were filled with vilification, drawing a villainous light toward the police force that investigated the murder Avery had been accused of. That may be exactly how everything happened in reality, yet the filmmakers still chose to use ten hours worth of new and old footage to create a very specific bias, despite having said at the beginning of the documentary that it was middle of the road.
There is a Kentucky Fried Chicken commercial that aired some years ago. While watching TNT one evening, I saw the commercial. The premise is "lady brings fried chicken home for dinner". The mom plops the chicken bag on the counter, plates it (because we all plate bucketed fried chicken when we dine at the table, am I right?), two children sit down, and then the father. It's standard stuff, really. I get hungry thinking about it.
Now, here comes the "media literacy" part. On a separate evening, I'm watching BET and I see a similar house, a similar setup, "lady brings fried chicken home for dinner", and I'm about to start hearing my stomach growl. Only, this commercial is different. The family before were a white couple with a boy and a girl. The woman in the BET ad is black and walks into the kitchen, running through the same scenario. Only, after the children sit down at the dinner table, the father never appears. Not only does the father never appear, the behavior of both the mother and her children are vastly different than that of the TNT commercial.
You see, in the TNT commercial, the white family was happy, smiling, grabbing chicken like the walls are made of drumsticks. Whereas in the BET commercial, the mother sits solemnly and the children have the doe-eyed, A Christmas Carol's "Tiny Tim" look on their face as if they should be grateful for every scrap.
This type of scenario is where media literacy can help. While the commercials target their demographics (white people, black people), they are also playing into cultural stereotypes. Not every white family has both a mom and a dad. Not every black family has an absentee father. Without media literacy, these types of commercials go unnoticed to the untrained mind because... because chicken is delicious. We must have the chicken. I see they're eating mashed potatoes, too. I'm comfortable with this representation of my skin color because it's what is expected of my race, and holy shit that chicken is crunchy and delicious...
This is the media playing tricks on your mind due to products, logo's, foods, ideas, cars, etc. This kind of marketing became prevalent in the 1950's when marketing execs realized the general public are easily manipulated. Ad executives found ways of manipulating their audiences into buying toothpaste that's ten cents more expensive because the person brushing in the commercial had pearly, white teeth. They got past your bullshit radar. Gaining media literacy is like regaining your bullshit radar. You know when someone's fucking with your head, to put it into terms my mother won't be happy about.
While documentaries like Making A Murderer, Forks Over Knives, Hungry for Change and Exit Through the Gift Shop are informational and entertaining, put a more guided focus on the latter when you watch anything meant to inform. Exit Through the Gift Shop is an excellent example of how easily filmmakers can create their own narrative through footage and archival information from the real world. While it is easily the most unrealistic documentary of those listed above, the way in which Banksy and his fellow artists assembled the near-mockumentary shows just how easily someone (the media) can sensationalize real-life events and make them seem much more grand in scale.
The biases are there. You need the training to see them. That training is called Media Literacy. It's like reading a book, but for tv, social media, also books, anything meant to communicate an idea to an audience. While you can learn Media Literacy quite easily, what you will fight yourself with most is putting into action the skills you've been taught as you make your way through the information super-highway day-to-day.
Media Literacy is so necessary with the kind of information-based technologies we have literally at our fingertips any moment of the day. A Google search of "Media Literacy" will provide you with a starting point to begin indoctrination of the rules and psychology behind the study of information, news, and entertainment media. I highly recommend studying media literacy.