Author: Dr. Keith Still, Director at Crowd Risk Analysis Ltd, author of Introduction to Crowd Science and Applied Crowd Science
Martyn’s Law, officially the Terrorism (Protection of Premises) Act 2025, became law in the UK on April 3, 2025, to enhance security at public venues and events against terror attacks. Named after Manchester Arena victim Martyn Hett, it mandates that venues with capacities of 200+ (standard) or 800+ (enhanced) implement security measures, staff training, and risk assessments to improve safety and preparedness. Although a UK Legislation, the principles embedded in the Act have implications for all places of public assembly.
Societal risks increasingly emerge not from single failures but from the interactions among people, places, and information. Martyn’s Law, the Terrorism (Protection of Premises) Act 2025, reflects this reality. While often framed as a security or compliance duty, its deeper implication is cultural: it asks public authorities and venue operators to rethink how risk is understood, communicated and acted upon in crowded public environments.
At its core, Martyn’s Law recognises that preparedness is not solely about physical measures, but about human behaviour and shared awareness. Crowds are not passive masses; they are dynamic systems shaped by perception, trust, and information flow. Poorly designed communication can amplify fear, delay response, or even create secondary harms, while well-timed, credible information can stabilise behaviour and support collective safety.
- Information as a Public Value Asset
Crowd information and crowd behaviour are closely linked. What a crowd understand about a situation is often treated as an operational by-product rather than a strategic asset. Yet public value is increasingly created or lost at this interface. In an emergency, authorities must make decisions amid uncertainty, often with incomplete data and intense time pressure. In these conditions, clarity of communication becomes as critical as accuracy.
Martyn’s Law implicitly elevates the importance of intelligible, proportionate messaging. The legislation promotes readiness rather than alarm, and this distinction matters. Over-securitised language risks eroding public trust, while under-communication can leave individuals unprepared. The challenge for public sector leaders is to design communication strategies that inform without alarming, guide without controlling, and respect the diversity of audiences present in public spaces.
- Mass Communication and Trust Under Pressure
Mass communication during incidents or heightened risk periods is not neutral. Messages compete with social media, rumours, and individual interpretation. Once released, they cannot be fully controlled. This creates a paradox: authorities are expected to communicate quickly yet are judged harshly for perceived inaccuracies or shifts in guidance.
Here, societal risk is not only the threat itself, but the erosion of institutional credibility. Martyn’s Law places responsibility on organisations to think in advance about how they would communicate in a crisis. This is less about scripts and more about principles: transparency, consistency, and empathy. Communication that acknowledges uncertainty can be more stabilising than false certainty.
- Decision-Making Across Disciplines
One of the strengths of Martyn’s Law is its accessibility. It does not require specialist expertise, but rather collaboration across security, communications, operations, and community engagement. This interdisciplinary approach is essential. Risk professionals may focus on threat scenarios, while communications specialists understand audience perception, and local authorities bring contextual knowledge of their communities.
Public value emerges when these perspectives are integrated, not siloed. Decisions informed by crowd information and communication insight are more likely to be proportionate, legitimate, and effective. Conversely, ignoring the social dimension of risk can lead to technically sound but socially fragile outcomes.
- AI and Mass Communications
AI can support mass communication by tailoring messages at speed. Often, different messages in different parts of a facility need to be broadcast simultaneously. Relying on an individual to convey important safety information in an appropriate tone has been the weakness of PA announcements. Used responsibly, AI helps authorities communicate clearly under pressure for emergency broadcasts. This technology exists now, with AI system assessing and reacting to situations.
Concluding Reflection
Martyn’s Law should not be viewed narrowly as a counter-terrorism measure. It is a prompt to rethink how public institutions understand societal risk in crowded places. Crowd information and mass communication are not secondary considerations; they are central to how safety, trust and public value are created in practice. The real test will not be compliance, but whether authorities can translate preparedness into communication that genuinely supports people when it matters most. The use of AI brings the problem of crowd communication into focus. Coupled with crowd science, this used to be the stuff of science fiction, but now it is part of standard operations practice.