Different types of Bias: Bias by Omission

By Dave Van Zandt – Media Bias Fact Check

Today I am going to cover one bias term that most understand, but may not recognize as almost every source employs it. I will cover other terms one by one in the future in an effort to help others understand the different methods of bias. This is part 1 of hopefully a weekly series…

When we review and rate media sources for bias we look at some very specific things to make our determination. One of the most important is the use of loaded words (words that convey emotion to sway the reader). That is always the first aspect of our source review.

We then proceed to the next most important part of bias, which is story selection. You often see in our reviews a statement such as this: “This source always publishes information that favors the left and is opposed to the right.” This means two things: 1. They use loaded words favorable to their bias and 2. They are selective in the information they publish. This leads us to our bias term for this article. Bias by Omission.

First, let’s define it: Bias by Omission- leaving one side out of an article, or a series of articles over a period of time; ignoring facts that tend to disprove liberal or conservative claims, or that support liberal or conservative beliefs. Or put another way they are leaving out information that would not be favorable to support their bias.

Bias by Omission can be seen daily on many right and left wing websites. For example, the day after President Trump was inaugurated there was the largest woman’s protest march in history. On almost all least biased and left leaning media sites this was the lead story. However, on the right biased Fox News it was buried at the bottom of the page, with many smaller news items getting more attention than this story.  We are not picking on Fox News, as Left leaning sites such as CNN also downplay news that is not favorable to the left. For example, there was a very large anti-abortion march in Washington DC last year. It got very little attention outside of right wing media. There are simply too many examples. It happens daily on all biased websites.

In other cases, we have sources that will not report anything positive from the other side. This is classic bias by omission. Further, sometimes sites use bias by omission in individual articles by leaving out key facts that change the context to favor one side. This is done in most articles that come from the left or right. A great example of bias by omission comes from the current FBI Memo issue. The Right’s memo is alleged to have left out many pieces that distort the factual context of events. While the Democratic memo has not been released yet, it is sure to change the context in a similar way. Watch for it and see what both sides left out to make their biased point. Sometimes what they don’t say gives more info than what they do say.

When evaluating a source, look for Bias by Omission. It will give you a good idea where this source leans and what their motivations are.

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2 Comments on "Different types of Bias: Bias by Omission"

  1. Why do bias-checkers resort to “bothsidesism” and false equivalence?

    Just like bias by omission, there is bias by overstating that goes hand in hand. Exaggerate one side, downplay the other, and while you have covered both, you have managed to be biased against the less egregious side.

    If there are a 100 stories that taint one side, and just 5 that taint the other, it is dishonest, if you take 2 from each, unless they are the top 4 scandals.

    march for life 2017 DID get coverage in the “left”
    CNN: http://www.cnn.com/2017/01/27/politics/trump-march-for-life-call/index.html
    NPR: https://www.npr.org/sections/thetwo-way/2017/01/27/511992534/demonstrators-descend-on-d-c-calling-for-end-to-legal-abortion
    Reuters: https://www.reuters.com/article/us-usa-abortion-march/pence-fires-up-anti-abortion-activists-in-washington-march-idUSKBN15B1ME
    Slate: http://www.slate.com/articles/double_x/doublex/2017/01/a_triumphant_mood_at_the_anti_abortion_march_for_life.html
    LAT: http://www.latimes.com/nation/la-na-crowd-sizes-20170127-story.html
    NYT: https://www.nytimes.com/2017/01/27/us/politics/march-for-life.html?mtrref=www.google.com&gwh=D82FF0FA0653964434FCD8AE079A66BA&gwt=pay
    The Atlantic: https://www.theatlantic.com/politics/archive/2017/01/march-for-life-trump/514679/
    Politico: https://www.politico.com/story/2017/01/march-for-life-2017-trump-supports-234267

    As a contrast, find rightwing media reporting the news on the women’s march. The RTL marches are not even new, 40+ have been conducted.

  2. Gosnell movie about an abortion doctor that killed thousands, perhaps tens of thousands of both born and unborn babies was refused coverage on left leaning NPR and nearly all other left leaning media, even though it had the highest funding record for crowd sourced movies. When we fool ourselves into thinking that we would stand up against slavery when it was legal – well in 100 years time most people will look back and ask how could people think abortion was OK in 2018 with all the evidence available to them which scientifically confirms that an unborn baby is unequivocally a human being. BIAS BY OMISSION, I SUSPECT.


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