Martyn's Law
Terrorism (Protection of Premises) Act 2025
Martyn’s Law will affect a significant number of publicly accessible premises and qualifying events across the UK, bringing new legal duties for an estimated 155,000 Standard Tier premises and approximately 24,000 Enhanced Tier premises.
Its purpose is straightforward: to improve public protection by ensuring that those responsible for publicly accessible premises and qualifying events give proper consideration to the threat of terrorism and take proportionate steps to prepare for it.
The legislation has generated significant discussion, confusion and, in some cases, misinformation. Much of the commentary currently circulating risks either overstating what is required or oversimplifying what meaningful preparedness looks like in practice.
The purpose of this page is not to reproduce the full legislative guidance, but to provide practical clarity and explain how I can assist organisations in preparing proportionately and effectively.
Regulatory Implementation
Martyn’s Law received Royal Assent in April 2025.
The Home Office published its Section 27 Guidance in April 2026, providing detailed clarification on scope, tier thresholds and practical interpretation.
The Security Industry Authority (SIA) has been appointed as the regulator, with full implementation currently expected in April 2028.
There is no legal requirement to comply with Martyn’s Law until the Act comes into force.
Once the Act comes fully into effect, many in-scope premises and events will technically fall into non-compliance immediately, either because they are not yet fully prepared or because they will not yet have had the opportunity to submit the required documentation. The SIA has acknowledged the practical challenge this creates, particularly given the volume of submissions expected and the fact that formal submissions cannot be made before the legislation goes live.
The regulator has indicated that implementation will be approached proportionately, allowing organisations reasonable time to prepare and demonstrate progress.
The SIA has also made clear that enforcement, where necessary, will follow a staged approach, with initial emphasis on support and compliance before escalation to formal sanctions in cases of serious or persistent non-compliance.
No formal timeframe has been specified, but the clear expectation is that organisations should be able to evidence meaningful preparation and take active steps towards compliance once the legislation is live and formal submission routes are available. With a minimum twelve-month period between publication of the Section 27 Guidance and full implementation, organisations have a valuable opportunity to prepare early and avoid unnecessary pressure closer to commencement, strengthening resilience and better protecting those who use their premises and events.
Understanding the Two Tiers
Standard Tier
Where premises fall within scope of the Act, Standard Tier generally applies where it is reasonable to expect between 200 and 799 individuals to be present at any one time.
If you are part of a recognised governing body or trade association, sector-specific guidance may already be available to help determine whether your premises fall within scope.
For Standard Tier premises, the focus is procedural rather than infrastructure-led.
This means having clear, site-specific procedures for:
- Evacuation
- Invacuation
- Lockdown
- Communicating effectively with those on site during an incident
The government’s position is that Standard Tier compliance should not ordinarily require expenditure on physical mitigation measures, with costs expected to arise primarily through management and staff time spent developing, testing and embedding effective procedures.
Staff awareness and training are essential. Procedures are only effective if those expected to implement them understand their roles during an emergency, have confidence in the process, and can act decisively under pressure.
Government guidance anticipates that many organisations will be able to develop these procedures themselves using resources already available through ProtectUK and the National Protective Security Authority (NPSA).
Martyn’s Law is not intended to be a simple compliance exercise. Procedures must be practical, relevant to the site, and capable of working in reality.
Whilst Standard Tier duties are primarily procedural, site-specific circumstances may indicate that additional proportionate protective measures should also be considered where justified.
Enhanced Tier
Where premises or qualifying events fall within scope of the Act, Enhanced Tier generally applies where it is reasonable to expect 800 or more individuals.
Enhanced Tier requirements include the same procedural obligations as Standard Tier, but also require:
- A terrorism risk assessment
- Consideration of vulnerabilities and attack methodologies
- Assessment of proportionate public protection measures, including monitoring, movement control, physical security and information security
- Documentation of procedures and measures
- Ongoing review of protective arrangements
These requirements are inherently more complex and require considered, site-specific assessment of procedural, operational and physical protective measures, often supported by appropriately qualified specialist external advice.
A notable exception applies to schools and places of worship. Regardless of attendance numbers, and regardless of whether parts of the premises may occasionally host larger qualifying events, these premises remain within the Standard Tier.
However, this does not remove the expectation for proportionate additional protective measures where site-specific threat factors justify them. Where there is a known elevated terrorism-related risk, additional physical or operational mitigations must still be considered.
Accountability
Both tiers require clear accountability through the designation of a responsible person, which in many cases will be the business entity itself.
For Enhanced Tier premises and events where the responsible person is not an individual, there is an additional requirement to designate a senior individual responsible for ensuring organisational compliance.
Clear ownership of these responsibilities is essential. Responsibility under the Act cannot be subcontracted to another person or entity.
Proportionate Preparedness
A key principle underpinning Martyn’s Law is proportionality.
Protective measures are expected to align with the principles of JASPAR:
- Justifiable
- Achievable
- Sustainable
- Practical
- Affordable
- Reasonable
Alongside this sits the principle of ALARP — reducing risk to a level that is As Low As Reasonably Practicable.
Whilst government impact assessments provide indicative cost assumptions, actual resource requirements will vary significantly depending on the maturity of existing arrangements, the complexity of the premises or event, and whether proportionate protective measures are already in place.
Every venue is different. Measures that are entirely appropriate for one site may be unnecessary, disproportionate or ineffective for another.
Beyond Formal Scope
Premises accommodating fewer than 200 individuals, or otherwise falling outside formal scope, are under no legal duty under the Act.
However, this does not mean that smaller-capacity premises are immune from terrorism or other serious hostile threats.
Many out-of-scope organisations may still benefit from proportionate measures that improve resilience and strengthen emergency preparedness where appropriate.
Common Practical Questions
The formal guidance is well considered, clearly structured and comprehensive. It provides multiple practical examples and addresses many of the nuances relevant to different types of premises and events within scope.
Questions frequently arise around:
- Whether a site or event falls within scope
- Which tier applies
- The extent of procedural planning required
- Whether existing arrangements are sufficient
- When additional mitigations are justified
- How proportionality should be interpreted in practice
- Who holds responsibility where a qualifying event takes place at an in-scope premises
There is no universal template, and no individual product, system or mitigation that can properly be described as “Martyn’s Law compliant” in isolation.
Preparedness must always reflect the specific realities of the premises or event, its operational use, and its risk profile.
Regulatory scrutiny will ultimately focus on whether arrangements are appropriate, proportionate and effective in the context of the circumstances.
How I Can Help
Drawing on over 30 years in protective security, together with advanced study in Terrorism Prevention and Management as well as Counter Terrorism Protective Security and Preparedness, I provide independent and practical support to organisations preparing proportionately for Martyn’s Law.
This includes:
- Determining scope and likely tier applicability
- Reviewing existing arrangements and documentation
- Developing or refining procedural plans
- Supporting terrorism risk assessments
- Identifying proportionate mitigation options
- Supporting training, exercising, testing and validation of procedures
- Providing independent advisory oversight
- Assisting with specification review and supplier evaluation where physical measures are required
Where internal capability or capacity is limited, external support can provide practical clarity and assurance without removing organisational responsibility under the Act.
The objective is not to recommend unnecessary complexity or expenditure, but to ensure arrangements are realistic, effective and capable of standing up to practical scrutiny.
A Practical Approach
Martyn’s Law should not be approached as a last-minute compliance exercise.
Done properly, it is an opportunity to improve preparedness, ensure that procedures will work in practice should they ever be needed, and strengthen organisational resilience.
If you would like advice on Martyn’s Law, wider terrorism preparedness, or your broader protective security arrangements, please feel free to get in touch for an informal discussion.