Media Matters for America was
founded in May 2004 by
David Brock, a former conservative journalist who has
since become a prominent Democratic party political
operative. Brock said that he founded the organization
to combat the conservative journalism sector that he had
once been a part of, although some critics say he has
simply adopted the tactics of his part for a new
political side. Brock further explained his motives for
starting the group, telling The New York Times, that
"the central thrust of his group would be to closely
monitor conservative commentators and journalists and,
when they make erroneous or misleading claims, to point
them out and set the record straight."
Brock said he founded the organization because conservative "monitoring groups have helped build the conservative media's influence, in part by making mainstream journalists toe a more conservative line by convincing them that they are liberally biased... The right wing in this country has dominated the debate over liberal bias. By dominating that debate, my belief is they've moved the media itself to the right and therefore they've moved American politics to the right." He added, "I wanted to create an institution to combat what they're doing."
Brock founded the group with help from the Center for American Progress. Initial donors included Leo Hindery, Susie Tompkins Buell, and James Hormel.
Media Matters analyzes American news sources including NBC, ABC, CBS, PBS, CNN, MSNBC, CNBC, OAN, Breitbart, the Fox News channel, and conservative talk radio. Its techniques include content analysis, fact checking, monitoring, and comparison of quotes or presentations from media figures to primary documents such as Pentagon or Government Accountability Office reports.
Beginning in 2006, Media Matters for America has released a number of studies which documented that Democrats and progressives are outnumbered by Republicans and conservatives in terms of guest appearances on television news programs.
On September 12, 2007, Media Matters released a comprehensive study of 1,377 U.S. newspapers and the 201 syndicated political columnists the papers carry on a regular basis. Media Matters said "in paper after paper, state after state, and region after region, conservative syndicated columnists get more space than their progressive counterparts."
John Diaz, editorial page editor of the San Francisco Chronicle, said by over-factoring conservative columns in smaller newspapers, Media Matters' study had overestimated how many conservative columns appeared in daily newspapers. Diaz said Media Matters had obscured the nuanced ideological positions of some columnists classified in the study as conservative.
An annual feature on the Media Matters website is the title of "Misinformer of the Year", which is given to the journalist, commentator, or network that Media Matters contends was responsible for the most factual errors or claims. Recipients of this award have included: Bill O'Reilly, Chris Matthews, ABC, Sean Hannity, Glenn Beck, Sarah Palin, Rupert Murdoch, Rush Limbaugh, CBS News, George Will, The Center for Medical Progress, the fake news ecosystem, and the alt-right.