Digital media is a platform of immediate presence that rests on a demediatized communication. It favors virtual collective action that allows digital citizens, in contexts of accentuated social inequality, to construe themselves as anti-establishment. Our research explores the co-participative construction of an online shitstorm, in comments posted on websites generated to respond to power abuse and inequity in Chilean society. The construction of citizens' anger in digital discourse will be analyzed in light of the postulates of Systemic Functional Linguistics (SFL) and in the perspective of Critical Discourse Analysis (CDA). The corpus analyzed consists of 500 comments issued between April and July 2016 to contest a powerful Chilean businessman who uploads a video to YouTube to defend himself from the public verbal attacks of a congressman. The results of the analysis show representations related to corruption, power abuse and inequity from people who conceal in the economic power they have to assert they are ordinary citizens.