This master thesis asks the question “Why are confessions so convincing?”. To provide an answer, I use Austin’s speech act theory to investigate how confessions work within the context of Swedish law. This model was fit for purpose; however, the theory lacks a temporal dimension necessary to understand the mechanisms in play when confessions convince someone. To account for this discrepancy, I use Derek Beach’s process tracing. Given the sometimes-strained relation between law and rhetoric I completed extensive reviews of literature on judicial rhetoric, both historically and contemporary. The current literature suggests that Swedish scholars of law use rhetorical theories more often than expected, however, Swedish scholars of rhetoric seem to interact with law a lot less. One of the findings of this thesis is that a rhetorical perspective, and the perspective from someone outside the field of law, may add significantly to understandings of confessions. Confessions are culturally important and often misunderstood, initially perceived as an unavoidable part of human nature. However, as discussed in this text, confessions are not rooted in human nature, but in cultural conventions, with a historical tradition dating back to the Middle Ages. When researching confessions in general, this paper identifies tensions between three kinds of confessions: religious confessions, juridical confessions, and psychotherapeutic confessions. Ten Swedish judges were interviewed, and 1599 court decisions were analyzed for this paper. Through this material an agreed upon ritual in which confessions become convincing appears. This ritual is however not the only reason why confession become convincing. Confessions can be detailed, coherent, and nuanced, which makes them more believable. The power to convince through confession consists of a complex net of different mechanisms, some based in the law system, and some based in rhetoric.