<p>  </p> <p>We cannot fully assess the normative and epistemic implications of online discourse, especially political discourse, without recognizing how it is being systematically leveraged to undermine the credibility and autonomy of those with marginalized identities. In the following chapters, I supplement social/feminist epistemological methodologies with norm theory to argue that online discourse entrenches the mechanisms of political dominance and cultural hegemony by ignoring and devaluing the experiences and struggles of marginalized individuals. Each chapter investigates a different, concrete manifestation of this dynamic. In Chapter 1, I argue that digital capitalist enterprises like Facebook facilitate the targeting of minoritized users with disproportionate instances of abuse, misinformation, and silencing. This is exemplified by the practice of using racial microtargeting to engage in Black, Indigenous, and People of Color (BIPOC) voter suppression. I contend in Chapter 2 that, given the exploitative nature of racially-microtargeted political advertising campaigns, these social media companies are ultimately morally responsible for initiating and sustaining a burgeoning digital voter suppression industry. In Chapter 3, I argue that the presence of online disinformation, in tandem with key party figures’ explicit endorsement of vicious group epistemic norms like close-mindedness and dogmatism, have directly contributed to the formation and epistemic isolation of conservative political factions in the US. Finally, I argue in Chapter 4 that social media and hostile media bias rhetoric directly reinforce sexist and racist credibility norms, effectively creating a toxic environment of misogynistic online discourse that hurts the perceived credibility of women journalists.</p>