Martyn's Law overview
The Terrorism (Protection of Premises) Act 2025 or as it is more commonly known ‘Martyn’s Law’ received Royal Assent on 3 April 2025, with statutory guidance published in April 2026.
Its introduction represents one of the most significant developments in UK counterterrorism planning in recent years. The Act places new duties on organisations and individuals with control or responsibility for publicly accessible premises or events to:
- assess terrorism risk;
- implement proportionate protective security measures; and
- ensure they can respond effectively to a terrorist incident at their premises or events.
At Weightmans, our multidisciplinary specialists are already supporting clients within the public and private sectors to prepare for compliance. With expertise across regulatory frameworks, regulatory risk and operational resilience, we provide clear, practical guidance to help duty holders understand their obligations and put workable measures in place.
We will also be on hand to help individuals and organisations identified as a ‘Responsible Person’ or ‘Designated Senior Individual’ under the Act to register with the regulator, the Security Industry Authority, when the time comes.
Understanding the Tiers Under Martyn’s Law
The Terrorism (Protection of Premises) Act 2025 applies to:
- Qualifying publicly accessible premises with an expected capacity of 200 people or more
- Qualifying public events with an expected capacity of 800 or more people
The duty imposed on those premises and events within scope is split into two tiers, Standard and Enhanced.
Standard tier – this duty applies to qualifying publicly accessible premises with an expected capacity of 200-799 people. The duties imposed on standard tier duty holders are intended to be proportionate, low cost procedural measures focused on responding to an incident.
Enhanced tier – this duty applies to all qualifying premises or events with an expected capacity of 800 people or more. Duty holders of enhanced tier premises or events are required implement measures to prevent incidents at their venue / event as well as measures to respond effectively in the event of an attack which may include physical measures.
How Weightmans Can Help
Our highly skilled team can assist duty holders with the following:
- Providing advice to prospective dutyholders on their legal obligations including whether premises or events potentially fall within scope and if so, which tier.
- Advice on responsible person and multiple responsible persons.
- Providing assistance with implementing measures as required by standard tier/enhanced tier obligations.
- Registering a dutyholder with the regulator, the Security Industry Authority.
- Representations to the regulator or the Tribunal on application of the legislation.
- Representing clients under investigation by the regulator.
- Responding to enforcement notices or fixed penalties including appealing those notices/penalties.
- Representing dutyholders subject to criminal prosecution under the Act. Training and awareness – producing materials and delivering training to support staff readiness and response.
Our Martyn’s Law Experts
Elliott Kenton, Partner – Regulatory
Elliott specialises in criminal and regulatory matters He principally advises organisations on all aspects of regulatory risk, including health and safety compliance, and business crime risk. Elliott is the lead partner for the internal investigations practice, and assists organizations in responding to incidents or other trigger events through the conduct of legally privileged investigations. Since the introduction of Martyn’s law, he has worked with a number of dutyholders providing practical advice on the applicability of the law, and where the law does apply, assisting organisations prepare for the law’s full implementation.
Paul Tarne, Partner – Local Government
A recognised adviser to local authorities and public bodies, Paul supports organisations with governance, statutory duties and risk management. His work includes scenario planning, security governance reviews and multi‑agency preparedness across diverse estates. Paul represented the Greater Manchester Combined Authority, including Greater Manchester Fire and Rescue Service, a Core Participant, as their designated legal representative in the Public Inquiry into the Manchester Arena Terror Attack, which precluded the introduction of Martyn’s Law.
Donna Helgeson, Principal Associate – Regulatory
Donna specialises in regulatory compliance and safety‑critical regimes. She regularly advises duty holders on regulatory compliance and assists duty holders following safety incidents and regulatory enforcement action. This can involve providing reactive advice on the likelihood of enforcement action / prosecution following alleged breaches of duty under H&S laws or other regulations (which will include those duties under Martyn’s Law) or proactive advice and training on the applicability of Martyn’s law and how to ensure better compliance with its requirements. When the enforcement regime is up and running, Donna will also be able to advise and represent Responsible Persons in relation to any enforcement action and civil sanctions taken against them by the regulator and related appeals against enforcement.
Rosanne McNeil – Regulatory
Rose is a regulatory lawyer specialising in advising individual, public sector, corporate, and insurer clients in respect of criminal and regulatory investigations following serious health and safety incidents. She represents clients facing investigation and prosecution for regulatory and criminal offences including motor crime, health and safety, neglect, and gross negligence/corporate manslaughter.