New ADL Report Finds Evidence of Biased, Coordinated Campaign on Wikipedia Related to the Israeli-Palestinian Conflict

New York, NY, March 18, 2025, …  Through an extensive investigation, ADL (Anti-Defamation League) Center for Technology and Society (CTS) researchers found widespread antisemitic and anti-Israel bias on Wikipedia, including clear evidence of a coordinated campaign to manipulate Wikipedia’s content related to the Israeli-Palestinian conflict, in likely violation of Wikipedia’s policies.

The report further found that pro-Hamas perspectives inform Arabic-language Wikipedia content on the Israeli-Palestinian conflict. 

“Most readers assume Wikipedia is a reliable online encyclopedia, but in reality, it has become a biased platform manipulated by agenda-driven editors on many topics,” said Jonathan Greenblatt, ADL CEO. “Recent Wikipedia efforts toward neutrality are nothing but a Band-Aid on a problem that’s getting worse, with persistent antisemitic and anti-Israel bias still far too present. We urge Wikipedia and policymakers to act quickly before rampant disinformation on one of the most visited sources of information leads to tragic consequences.”

Coordinated anti-Jewish, anti-Israel bias and manipulation

ADL has found clear evidence that a group of at least 30 editors acted in concert to circumvent Wikipedia’s policies to introduce antisemitic narratives, anti-Israel bias, and misleading information:

• These 30 editors were much more active than other comparable groups of editors, on average, by a factor of at least two, based on total edits made over the past 10 years.
• The 30 editors were much more likely than other editors to communicate with each other on Wikipedia: they were as much as 18 times more active in group communications than comparable groups of editors.
• The editors appeared to coordinate to change pages related to the Israeli-Palestinian conflict, downplaying Palestinian antisemitism, violence, and calls to destroy Israel while promoting criticism of Israel.  
• These edits have ramped up since the October 7, 2023, Hamas attacks and include the systematic removal of citations to reputable sources and tandem voting to keep content critical of Israel but remove coverage of Palestinian violence and terrorism.  

“It’s clear that Wikipedia needs to do far more to address the very active antisemitic and anti-Israel bias and coordination,” said Daniel Kelley, Interim Head, ADL Center for Technology and Society. “And until then, other platforms that rely on Wikipedia as a source– from Google Search to large language models like ChatGPT – must deprioritize unvetted Wikipedia’s content on issues related to Jews, Israel and the Middle East conflict so that they do not perpetuate this bias.” 

Bias in Arabic-language Wikipedia content on Hamas

In addition to this campaign of anti-Israel manipulation and disinformation found on English-language Wikipedia pages, Wikipedia’s policies are not adequately preventing widespread bias and partiality on its Arabic-language pages related to Hamas. ADL analyzed pages on the terrorist organization in Arabic and found that both the primary page and related pages glorify Hamas, perpetuate pro-Hamas propaganda, and flout Wikipedia’s rules for neutrality.  

Policy Recommendations

The report provides detailed recommendations for Wikipedia, companies like Google and those with LLMs, and for government, including:

For Wikipedia:

• Reputable expert program: Wikipedia should develop a program for experts on the Israeli-Palestinian conflict, vetted by the Wikimedia Foundation, to review contentious pages for accuracy and bias.
• Pre-screening special closure editors: For contentious topics on Israel and the Israeli-Palestinian conflict, a special committee of administrators should vet and appoint Wikipedia editors with the sole right to close talk page discussions concerning disputes about article content.
• Closure cannot be decided by a majority vote: Decisions on controversial content that become the subject of talk page discussions should be decided on the merits by specially designated closure editors, rather than by majority vote (as is the current policy but not always actual practice).
• Inauthentic behavior/state actors: Wikipedia should evaluate their existing tools against inauthentic behavior and foreign influence to determine whether they’re adequate to address current issues and concerns.

For Policymakers:

• Convene academics, Wikipedians, computer scientists, and civil society to draw recommendations and policy options for limiting bias and antisemitism on Wikipedia, including pushing for greater transparency and reporting requirements on efforts by Wikipedia to root out bias.
• Create a task force aimed at combating antisemitic bias on Wikipedia. 
• Hold hearings on the topic of bias and antisemitism on Wikipedia.
• Raise awareness with constituents and colleagues about bias and antisemitism on Wikipedia by writing public letters to the Wikimedia Foundation, highlighting issues and demanding answers on how they will work to ensure the site does not become a haven for hate.

The manipulation and disinformation problem on Wikipedia is wide-spread and touches multiple topics, highlighting the urgency of addressing this broad platform-wide issue. 

Recently, Wikipedia’s arbitration committee (ArbCom) banned several editors from the Israel-Palestine topic area (known as a topic ban, rather than a more comprehensive site-wide ban). A World Jewish Congress report on Wikipedia also detailed ongoing issues of anti-Israel and antisemitic bias on English-language Wikipedia, such as Holocaust revisionism. In one instance, a group of Polish editors appears to have engaged in coordinated efforts to insert a Polish nationalist narrative into articles on the Holocaust in Poland, downplaying Polish responsibility and blaming Polish Jews. Separately, there have also been similar campaigns to erase Native American history.

This research was conducted in partnership with Builders for Tomorrow (BFT), a venture philanthropy and research organization focused on combating anti-Jewish and anti-West ideologies.

ADL is the leading anti-hate organization in the world. Founded in 1913, its timeless mission is “to stop the defamation of the Jewish people and to secure justice and fair treatment to all.” Today, ADL continues to fight all forms of antisemitism and bias, using innovation and partnerships to drive impact. A global leader in combating antisemitism, countering extremism and battling bigotry wherever and whenever it happens, ADL works to protect democracy and ensure a just and inclusive society for all. More at www.adl.org.