Visual data are transforming the documentation of activities across many legal domains. Visual data can incriminate or exonerate; they can shape and reshape public opinion. Visual evidence can legitimize certain accounts of events while calling others into question. The proliferation of visual data creates challenges for the law at multiple points of entry: recording, distribution or disclosure, redaction or deletion, or use as evidence. This symposium outlines and analyzes legal challenges posed by recent developments in visual data technologies and practices. This introductory essay and the articles that follow highlight legal issues that arise when state actors collect visual data and when visual data are used in legal disputes. Technological development is outpacing empirical research on, and legal regulation of, visual data within society and inside the courtroom. This symposium provides a much-needed opportunity to highlight new legal and empirical research at the intersection of visual data and law.