Which US news sources have been accused of having a liberal or conservative bias by media watchdog groups?

1. Fox News: a frequent target of progressive watchdogs

Academics, media figures and progressive watchdog groups have described Fox News as biased toward the Republican Party and conservative viewpoints, with Media Matters and FAIR cited as critics who argue the network embeds conservative editorializing into news coverage and has misled audiences on subjects like climate and COVID-19 ^{[1] [2]}. Media Research Center affiliates and conservative commentators defend Fox as populist and assert it “tilts right” without being an active campaign organ, a framing that highlights competing interpretations of the same behavior ^[1].

2. NPR and Politico: mainstream outlets accused from both sides

NPR has been accused of bias by both conservative pro-Israel group CAMERA and the progressive FAIR—illustrating how a single outlet can draw charges from opposite directions—and academic studies such as those by Groseclose and Milyo have also been cited as finding a liberal tilt in public broadcasting, while audience surveys show NPR’s listeners lean liberal, a fact watchdogs use to substantiate claims ^[3]. Politico has likewise been accused by Media Matters of a “Republican tilt,” even as other assessments rate it as relatively balanced and audience surveys show mixed leanings, underscoring that accusations often depend on the critic’s viewpoint and methodology ^[7].

3. Right-leaning outlets identified by conservative and centrist trackers

Websites and networks that rate political slant—such as AllSides and Media Bias/Fact Check—consistently place organizations like The Center Square and other right-leaning outlets in a right or right-center category, with MBFC explicitly describing The Center Square as “Right-Center Biased” while noting funding transparency as a factor in credibility ratings ^{[8] [5]}. These catalogues are used by both critics and defenders to argue that either mainstream media skews left or that a distinct conservative media ecosystem exists, depending on which slice of outlets one examines ^{[5] [9]}.

4. Watchdogs themselves have political identities and agendas

The groups making accusations are not neutral: Media Matters was founded as a progressive counterweight to conservative monitors and explicitly aims to counter conservative misinformation, while NewsBusters and Accuracy in Media serve conservative critique functions, meaning their lists reflect editorial missions as much as empirical audits ^{[2] [4] [1]}. FAIR frames accusations of liberal media bias as part of a conservative political strategy, demonstrating how even meta-claims about bias are contested territory ^[10].

5. Mapping bias: ratings, methodology disputes and the limits of lists

Aggregators and academic studies offer tools—AllSides’ Media Bias Chart, Ground News’ rating system, and university research guides—that place outlets along a spectrum and report audience trust differences, but these tools employ differing criteria (audience composition, content analysis, editorial positions), and scholars warn that methods can produce conflicting conclusions about whether the media are broadly liberal, conservative, or institutionally shaped by market incentives ^{[5] [6] [9] [11]}. A growing number of official trackers, including high-profile political offices and private platforms, have also launched “media bias” trackers and hall-of-shame style lists, which further politicize classification efforts ^[12].