Jon Stewart’s announcement that he’ll retire from “The Daily Show” later this year has inspired countless homages. Bill de Blasio praised the comedian for speaking “great truths in even his silliest jokes.” J.K. Rowling tweeted that “The Daily Show” was one of her “favourite TV programmes ever.” Even conservative talk show host Bill O’Reilly—one of Stewart’s most frequent targets—acknowledged him as “the standard-bearer on television for the liberal point of view.” 

But at least one ode rang false. At The Atlantic, David Sims wrote that Stewart’s “willingness to swipe at every hagiography or exaggeration presented by politicians and media alike made him the most trusted man on television in an era of profound cynicism.” But Stewart shouldn’t get a free pass, just because he’s funny: He did his part to foster that atmosphere of distrust and scorn. Hardly anyone—right or left, public figure or ordinary citizen—could assume they were exempt from his mockery. I’ve often found that watching Stewart attack everyone for half an hour can leave you feeling kind of hopeless.

Empirical research supports this idea. In 2004, Jody Baumgartner and Jonathan Morris, political scientists at East Carolina University, designed an experiment to look at how watching “The Daily Show” affected viewers’ feelings toward politicians of both parties. Baumgartner and Morris recruited 732 college students, and divided them into three groups. (In many experiments, relying on college students is a drawback—but in this case, it actually yielded a good stand-in for Stewart’s relatively young, educated audience.) One group was assigned to watch an eight-minute video made up of clips of Stewart covering the campaigns of John Kerry and George W. Bush; a second group watched a similar compilation of election coverage drawn from CBS’s “Evening News,” a representative of traditional mainstream media; and a final control group didn’t watch anything. 

Afterwards, participants were asked to rate both Kerry and Bush on several attributes, including honesty, competence, and leadership abilities. Baumgartner and Morris combined the ratings to generate a single score—and found that watching just eight minutes of “The Daily Show” left viewers across the political spectrum feeling much more negative about both candidates, whereas the CBS clip didn’t significantly affect viewers’ opinions of either candidate. 

Baumgartner and Morris asked members of the control group about their media consumption habits and attitudes toward the candidates and, interestingly, found that regularly watching the “The Daily Show” was the strongest predictor of lacking faith in the electoral system and distrusting the news media. Other comic-news shows, like “The Jay Leno Show” or “Late Show With David Letterman,” didn’t have the same effect.

Stewart isn’t the only comedian-pundit who hasn’t always furthered his own agenda. Baumgartner and Morris have also studied how watching “The Colbert Report” affects viewers’ political attitudes: They found, counterintuitively, that college students actually had more “warm” feelings toward George W. Bush after watching “Colbert” than “The O’Reilly Factor.”