Wikipedia is a free online encyclopedia that anyone can edit. The site acknowledges that "citation of Wikipedia in research papers may be considered unacceptable, because Wikipedia is not a reliable source," and is prohibited by policy of many educational institutions(2). A related Wikipedia essay notes:


“Wikipedia is not a reliable source...information it contains at any particular time could be vandalism, a work in progress, or just plain wrong. Biographies of living persons, subjects that happen to be in the news, and politically or culturally contentious topics are especially vulnerable to these issues...There are many errors that remain unnoticed for days, weeks, months, years, or even for a decade. Therefore, Wikipedia should not be considered a definitive source in and of itself.”(2)


A 2018 study published by Harvard evaluated articles in Wikipedia and Encyclopedia Britannica to “compare bias in these two models in the context of contested knowledge, which involves subjective, unverifiable, or controversial information.”(3) They found that “Wikipedia articles are more slanted towards Democratic views than are Britannica articles, as well as more biased.”


Wikipedia cites its internal policy that “articles must be written from a neutral point of view, which means representing fairly, proportionately, and, as far as possible, without editorial bias, all of the significant points of view that have been verifiably published by reliable sources on a topic.”(4) The site nonetheless acknowledges that as it relies on volunteer editors, it is susceptible to the ideological bias of its contributors, which has been alleged particularly for the English language version. It cites research findings that “articles with smaller edit volumes by a little number of ideologically homogeneous contributors were more likely to reflect an editorial bias.”(5),(6)


Many have noted Wikipedia articles’ mainstreaming of left-leaning or even far-left media and organizations by neglecting or minimizing mention of ideological bias and controversies surrounding bias and false reporting. Wiki articles have tended to marginalize independent, right-center, and conservative organizations by prominently representing claims of ideological bias and criticism from competitors on the political left as if they were factual and unbiased.


The article “Inside Wikipedia's leftist bias: socialism pages whitewashed, communist atrocities buried” notes that millions rely on Wikipedia for information, which is ranked by Alexa as the “13th most popular website in the world,” and is given special placement in Google search results.(7) Yet Wikipedia co-founder Larry Sanger complained that “many Wikipedia pages have become merely left-wing advocacy essays.” He stated:


"The days of Wikipedia's robust commitment to neutrality are long gone. Wikipedia's ideological and religious bias is real and troubling, particularly in a resource that continues to be treated by many as an unbiased reference work.”(ibid)


An example is cited of Wikipedia’s main articles on socialism and communism, which span 28,000 words with mostly flattering claims. These pages “whitewash crimes against humanity” in the USSR and China and “fail to note any of the atrocities committed by other socialist and communist regimes, from Venezuela, Cuba, Nicaragua, Cambodia, or North Korea, among others.”(ibid) Rampant human rights violations and atrocities including the murder of an estimated 100 million people are relegated to “a stray link at the very end under a ‘see also’ heading.” Economics professor Bryan Caplan noted that “The omission of large-scale mass murder, slave labor, and man-made famines is negligent and deeply misleading.” Jonathan Weiss, a top-100 Wikipedia editor, noted that “the political pages have largely been taken over by editors with a political axe to grind.”(ibid) Edits to add balance have been “quickly erased by other editors.”

In his book “Essays on Free Knowledge: The Origins of Wikipedia and the New Politics of Knowledge,” Wikipedia co-founder Larry Sanger noted that writing articles from a neutral point of view (NPOV) was one of Wikipedia’s five founding pillars as “no one has the right to make up your mind for you.”(8)  Sanger wrote in June 2021 that the neutrality policy was intended to avoid placing an “enormous amount of power in the hands of a ideological cabal,” which “would turn Wikipedia into an engine of propaganda.”(9)  Sanger examined Wikipedia articles on recent political topics and found them to be “extremely biased,” noting: “The articles are so biased, in fact, that it is fair to call them ‘propaganda.’” 


Sanger observed that Wikipedia engages in blatant ideological censorship, having “systematically purged conservative mainstream media sources” while permitting only “globalist, progressive” sources, many of which spread misinformation:


“Wikipedia does not just mirror the biases found in the mainstream news media, because some of it is conservative or contrarian.   A lot of mainstream news stories are broken only in Fox News, the Daily Mail, and the New York Post—all of which are banned from use as sources by Wikipedia. Beyond that, many mainstream sources of conservative, libertarian, or contrarian opinion are banned from Wikipedia as well, including Quillette, The Federalist, and the Daily Caller. Those might be contrarian or conservative, but they are hardly ‘radical’; they are still mainstream. So, how on earth can such viewpoints ever be given an airing on Wikipedia? Answer: often, they cannot, not if there are no “reliable sources” available to report about them. In short, and with few exceptions, only globalist, progressive mainstream sources—and sources friendly to globalist progressivism—are permitted.


“It is not too far to say that Wikipedia, like many other deeply biased institutions of our brave new digital world, has made itself into a kind of thought police that has de facto shackled conservative viewpoints with which they disagree. Democracy cannot thrive under such conditions: I maintain that Wikipedia has become an opponent of vigorous democracy. Democracy requires that voters be given the full range of views on controversial issues, so that they can make up their minds for themselves. If society’s main information sources march in ideological lockstep, they make a mockery of democracy. Then the wealthy and powerful need only gain control of the few approved organs of acceptable thought; then they will be able to manipulate and ultimately control all important political dialogue.”(9)

Wikipedia’s systematic exclusion of libertarian and conservative-leaning sources represent blatant ideological censorship. Claims that leftist sources are “authoritative” and that mainstream libertarian and conservative sources are unreliable are simply false. Media Bias Fact Check and other nonpartisan media rating websites notes significant problems with the reliability and bias of leftist outlets.  CNN and MSNBC, for instance, are rated as having only “mixed” factual accuracy and below “mostly factual:” the fourth of sixth possible rankings, with numerous factual errors and frequent “bias by omission.”  


Factual information from sources identified as right-leaning is systematically excluded, whereas partisan opinions from the left are uncritically represented as credible.  Wikipedia routinely cites left-leaning sources without identifying their biases.  Leftist academics and activists are frequently cited, ostensibly as objective observers, to disparage conservative organizations while their own biases are rarely if ever identified.



1. "Wikipedia: Academic Use." (accessed March 21, 2021). 

2. "Wikipedia:Wikipedia is not a reliable source." (accessed March 21, 2021).

3. Greenstein, Shane, and Feng Zhu. "Do Experts or Crowd-Based Models Produce More Bias? Evidence from Encyclopædia Britannica and Wikipedia." MIS Quarterly 42, no. 3 (September 2018): 945–959. 

4. “Ideological bias on Wikipedia.” (accessed March 21, 2021).

5. Greenstein, Shane; Gu, Yuan; Zhu, Feng (March 2017) [October 2016]. "Ideological segregation among online collaborators: Evidence from Wikipedians". National Bureau of Economic Research. No. w22744. doi:10.3386/w22744.

6. Holtz, Peter; Kimmerle, Joachim; Cress, Ulrike (October 23, 2018). "Using big data techniques for measuring productive friction in mass collaboration online environments". International Journal of Computer-Supported Collaborative Learning. 13 (4): 439–456. doi:10.1007/s11412-018-9285-y.

7. Lott, Maxim. “Inside Wikipedia's leftist bias: socialism pages whitewashed, communist atrocities buried.” February 18, 2021. 

8. Sanger, Larry. "Essays on Free Knowledge: The Origins of Wikipedia and the New Politics of Knowledge."  Sanger Press, September 19, 2020. 270 pp. 

9. Sanger, Larry. "Wikipedia Is More One-Sided Than Ever.", June 30, 2021.