Abstract. Comments sections under news articles have become popular spaces for audience members to oppose the mainstream media’s perspective on political issues by expressing alternative views. This kind of challenge to mainstream discourses is a necessary element of proper deliberation. However, due to heuristic information processing and the public concern about disinformation online, readers of comments sections may be inherently skeptical about user comments that counter the views of mainstream media. Consequently, commenters with alternative views may participate in discussions from a position of disadvantage because their contributions are scrutinized particularly critically. Nevertheless, this effect has hitherto not been empirically established. To address this gap, a multifactorial, between-subjects experimental study ( N = 166) was conducted that investigated how participants assess the credibility and argument quality of media-dissonant user comments relative to media-congruent user comments. The findings revealed that media-dissonant user comments are, indeed, disadvantaged in online discussions, as they are assessed as less credible and more poorly argued than media-congruent user comments. Moreover, the findings showed that the higher the participants’ level of media trust, the worse the assessment of media-dissonant user comments relative to media-congruent user comments. Normative implications and avenues for future research are discussed.