Viewing language as a system consisting of grammatical resources for meaning making, this study explores how agency and responsibility are attributed in legal narratives through the lens of transitivity. Drawing upon the opening address of three American trials, the quantitative and qualitative findings indicate that agency and blameworthiness of the individuals on trial are discursively negotiated through starkly different grammatical choices, so that polarized positionings of the same social actors and events are accomplished for the audience. It is argued that such manipulation of grammatical resources exhibits subjective intervention on the part of the presenter and constitutes a prime mechanism of inference and attitudinal evocation for the jurors. In effect, the opening statement, which is in principle intended to be merely informative, becomes not only argumentative but also evaluative.