This article explores the role of explicit or implicit argumentation in explaining, and accounting for, the views people form about political events; events of which, necessarily, they generally have only mediated knowledge. The media do not only inform people of the events which happen, but also exercise a role in forming opinions about those events. This may occur through selection of what is printed, but also in editorial comments or indirectly through framing strategies, use of evaluative language, and so on. The Skripal/Novichok case in 2018 offers a good opportunity to assess some of these points, since it provoked great press attention and public interest and, moreover, Britain's politicians advanced a specific theory relating to the guilt of the Russian state, and Putin's personal involvement. The paper attempts to probe how far people's opinions on the case depend on media exposure, and to explore patterns of evidentiality in the discourse of interviewees about the topic.