This can distort ability to weigh evidence in an objective manner and reaching a fair and accurate judgment. People can be biased and so can news sources.
How to spot media bias:
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.
Bias by Labeling: Bias by labeling comes in two forms. The first is the tagging of conservative politicians and groups with extreme labels while leaving liberal politicians and groups unlabeled or with more mild labels, or vice versa. The second kind of bias by labeling occurs when a reporter not only fails to identify a liberal as a liberal or a conservative as a conservative, but describes the person or group with positive labels, such as “an expert” or “independent consumer group.”
Bias by Placement: is where on a website (or newspaper) or in an article a story or event is printed; a pattern of placing news stories so as to downplay information supportive of either conservative views or liberal views.
Bias by Selection of Sources: including more sources that support one view over another.
Bias by Spin: is a reporter’s subjective comments about objective facts; makes one side’s ideological perspective look better than another.
Bias by Story Selection: a pattern of highlighting news stories that coincide with the agenda of either the Left or the Right, while ignoring stories that coincide with the opposing view.
Confirmation Bias: also called confirmatory bias or my side bias, is the tendency to search for, interpret, favor, and recall information in a way that confirms one’s beliefs or hypotheses, while giving disproportionately less consideration to alternative possibilities.
Connotation: the emotional and imaginative association surrounding a word that can be either positive or negative.
Denotation: the strict dictionary meaning of the word.
Loaded Language (Words): (also known as loaded terms or emotive language) is wording that attempts to influence an audience by using appeal to emotion or stereotypes. Such wording is also known as high-inference language or language persuasive techniques.
Purr Words: words used to describe something that is favored or loved.
Snarl Words: words used when describing something that a person is against or hates.