Systems of justice based on lay juries are meant to ensure a close link between the law and the community it serves: jurors represent the values of the community and these are fed back into the legal system. However, juries can only arrive at legally fair decisions if they have managed to understand and apply the law relating to the case. Yet legal systems in common law countries have paid scant attention to whether legal instructions delivered by the judge are actually conveyed effectively to the jury. This paper considers the process of jury instruction from linguistic and communicational perspectives. It draws a key distinction between ‘jury instructions’, or the legal texts produced by judicial committees and delivered by judges, and ‘jury instruction’, or the process of communicating the relevant law to a specific jury in the context of a specifictrial. While the comprehension of specific instructions can be improved by rewriting them in plain English, the overall process of instruction requires much more radical revision if one wants to ensure that lay juries will bring in true and just verdicts which reflect both the law and the values of the community.