December 14, 2005: Authors Tout Flawed Study as Proof of Media’s ‘Liberal Bias’

The authors of a new media study say that they were “surprised” to find how much of a “liberal bias” exists in the American press. The study will later be found to be fundamentally flawed in its methodology and its conclusions (see December 2004). Even the Wall Street Journal and the right-wing Internet media and gossip outlet the Drudge Report are liberally biased, authors Tim Groseclose and Jeffrey Milyo find. The most centrist media outlet of the ones studied is, the authors claim, PBS’s NewsHour with Jim Lehrer. The news report on the study, by the UCLA Newsroom, claims the report is “the first successful attempt at objectively quantifying bias in a range of media outlets and ranking them accordingly.” Groseclose says: “I suspected that many media outlets would tilt to the left because surveys have shown that reporters tend to vote more Democrat than Republican. But I was surprised at just how pronounced the distinctions are.” Milyo adds, “Overall, the major media outlets are quite moderate compared to members of Congress, but even so, there is a quantifiable and significant bias in that nearly all of them lean to the left.” The news report explains that the authors “based their research on a standard gauge of a lawmaker’s support for liberal causes. Americans for Democratic Action (ADA) tracks the percentage of times that each lawmaker votes on the liberal side of an issue. Based on these votes, the ADA assigns a numerical score to each lawmaker, where ‘100’ is the most liberal and ‘0’ is the most conservative. After adjustments to compensate for disproportionate representation that the Senate gives to low-population states and the lack of representation for the District of Columbia, the average ADA score in Congress (50.1) was assumed to represent the political position of the average US voter. Groseclose and Milyo then directed 21 research assistants—most of them college students—to scour US media coverage of the past 10 years. They tallied the number of times each media outlet referred to think tanks and policy groups, such as the left-leaning NAACP or the right-leaning Heritage Foundation. Next, they did the same exercise with speeches of US lawmakers. If a media outlet displayed a citation pattern similar to that of a lawmaker, then Groseclose and Milyo’s method assigned both a similar ADA score.” “A media person would have never done this study,” Groseclose says. “It takes a Congress scholar even to think of using ADA scores as a measure. And I don’t think many media scholars would have considered comparing news stories to Congressional speeches.” According to the study, the “leftward tilt” of news broadcasts by ABC and CBS is “nearly perfectly balanced” by the slight rightward tilt of Fox News. “Past researchers have been able to say whether an outlet is conservative or liberal, but no one has ever compared media outlets to lawmakers,” Groseclose says. “Our work gives a precise characterization of the bias and relates it to known commodity—politicians.” [UCLA Newsroom, 12/14/2005]