Trials have evolved into an adversarial process, and the state has taken over the prosecutorial function. There are five challenges to this ‘equality of arms’: expanded powers of the state to address a perceived imbalance between prosecution and defence; emergency provisions becoming part of normal law; the application of criminal law to deal with regulatory issues; the use of civil jurisdiction as a crime prevention strategy; and the accommodation of victims and witnesses within the system. Maintaining a balance between security and public protection on the one hand and strong due process safeguards on the other is a complex task. But keeping both perspectives in mind helps ensure that new measures are driven by evidence-based criteria and broad considerations of strategy.