Martyn’s Law is no longer a future concept—it is on the statute book, with enforcement  by the regulator (Security Industry Authority SIA) from April 2027. The question for the heritage sector is not what is it, but how prepared are you?

The legislation sets a clear expectation: organisations responsible for publicly accessible premises must be able to demonstrate that they have considered the risk of terrorism, put in place proportionate mitigation, and can respond effectively if the worst happens. This is a regulatory shift. It introduces accountability, oversight, and ultimately the potential for enforcement action where organisations cannot evidence preparedness.

If the SIA walked onto your site tomorrow, what would you show them?

Would you be able to demonstrate who your “responsible person” is? Could you explain how your organisation would respond to an unfolding incident—evacuation, lockdown, communication—without uncertainty? Would your staff and volunteers know what to do?

Martyn’s Law deliberately avoids prescribing expensive or overly complex solutions, particularly for smaller venues. Even for standard-tier sites, there is a requirement for clear, actionable public protection procedures and staff awareness. The days of having a generic emergency plan sitting on a shelf are over.

For heritage organisations, these questions are even sharper.

Many sites operate with open access models, minimal screening, and complex historic layouts. Some rely heavily on volunteers. Others are constrained by listed building status, limiting what physical measures can be introduced. These are valid challenges—but they are not exemptions. The legislation applies regardless of whether your site is a modern arena or a 900-year-old castle.

  • Do you understand where your vulnerabilities actually are?
  • How would you manage a fast-moving incident in a multi-building estate or open grounds?
  • How quickly could you communicate with everyone on site if something happened?
  • Have you tested this to check it works?

The intent behind Martyn’s Law is simple: improve preparedness and reduce harm. But from a regulatory perspective, the SIA will not be assessing intent—they will be assessing evidence. Can you demonstrate that you have thought about the threat, made informed decisions, and embedded proportionate measures?

The heritage sector is not starting from zero. Many organisations already have strong foundations in health and safety, emergency planning, and visitor management. The challenge is translating that into a counter-terrorism context—where unpredictability, speed, and hostile intent change the nature of the response required.

There is still time. The implementation window was designed to allow organisations to prepare. But that window is closing, and the organisations that delay are likely to face the hardest adjustments when enforcement begins.

How TIAA Can Help

TIAA supports heritage organisations to move from uncertainty to readiness—without losing sight of the unique constraints of historic environments.

  • Proportionate readiness assessments
    We help you understand your exposure under Martyn’s Law, test your current plans, and identify gaps before the regulator does.
  • Practical, heritage-sensitive solutions
    Our approach balances security, visitor experience, and conservation constraints—focusing on what is realistic, defensible, and effective.
  • Training and exercising
    We ensure your staff and volunteers are not just briefed, but prepared—through tailored training and scenario-based testing aligned to your site.

Sources: [gov.uk], [protectuk.police.uk]