This chapter explores the meaning of ‘trial by mediaTrial by media’ and points to the limited research that is available in this area. It also introduces the book’s argument that trial by media does not always take place in the context of ongoing court proceedings but often relates to issues that are not the subject of trial or litigation, making it the new normal in a digital realm in which media users are empowered to actively ‘investigate’, ‘prosecute’ and ‘punish’ deviant behaviour. The chapter foregrounds the idea that, despite its potentially harmful effects, trial by media can positively benefit the pursuit of justice. It also discusses the close link between trial by media and democratic participation in the administration of justice. Another focus of the book is the pre-digital origins of trial by media. The successful adaptation of legacy media to digital technology has led to new ways of attracting audiences, but it also marks a departure from the traditional mediation of crime and justice. The various risks and opportunities of mediated participatory mediaparticipatory media are also discussed in this chapter. A recurrent theme in this book is the importance of an enhanced ethical framework for both media professionals and digital media users to harness the benefits of participatory justice and minimise the drawbacks of trial by media.