Home Office publishes ‘Martyn’s Law’ venue guidance

The Terrorism (Protection of Premises) Act 2025 – known as ‘Martyn’s Law’ after Martyn Hett who died in the Manchester Arena bombing in 2017 – was promoted in the wake of the attack. It is intended to compel businesses to improve their emergency preparedness and take greater steps to reduce their vulnerability to acts of terrorism.

The law was given Royal Assent on 3 April 2025 and is due to come into effect around April 2027 after a 24 month implementation period. It requires those responsible for certain premises and events to take steps to prepare for and help keep people safe from terrorist attacks.

The Act covers “qualifying premises" which are publicly accessible locations primarily used for entertainment, leisure, retail, food and drink, museums, galleries, sports grounds, government buildings, visitor attractions, places of worship, health, and education establishments.

To be in scope of the Act, premises must also meet certain capacity thresholds, which will determine the steps required to be taken by dutyholders. “Standard duty premises” are defined as locations with a capacity of 200 to 799 individuals, while “enhanced duty premises” are locations where it is reasonable to expect 800 or more individuals to be present at the same time.

The Act provides that premises “consist of a building or a building and other land”. “Building” is said to include part of a building or a group of buildings. The guidance confirms that for a site to meet the definition of premises under the Act, there must always be a building on it that is accessible to the public. It is irrelevant that access may be limited only to certain members of the public – such as ticket holders, members of a club – or that individuals are expected to be present in the buildings, only gathered on the land outside, or a mixture of both. It also confirms that matters such as the geographical proximity of the buildings, that they share a principal in scope use or that the responsible person is the same for all or most of the buildings in the group, may all be indicative that there is a “group of buildings” for the purposes of the Act. 

As well as qualifying premises, the legislation also applies to "qualifying events." These are public events held at premises not classified as enhanced duty premises, but where 800 or more individuals may be present at the same time at some point during the event. For qualifying events, there is no need for the premises to contain a building.

One example given is of a stately home that is otherwise out of scope as a private residence hired by an event organiser to host a one-off festival may still be in scope for the duration of the festival if it meets the qualifying event criteria. Measures must also be in place to control access to such events. This means that to be in scope of the Act, open air events must have a well-defined and secure perimeter so that the required entry check is meaningful. That check must also relate to accessing the location or part of it where the event takes place, rather than the activity taking place there.

Determination of number of individuals that can reasonably be expected to be present at the same time (the reasonably expected capacity) is a key requirement of the Act. The guidance provides that the methodology used to assess this should be reasonable, evidenced and defendable and must include employees, contractors, volunteers and others working at the premises, or in the case of qualifying events, those attending or working in the part of the premises connected with the event. The reasonably expected capacity may change over time and so should be kept under review. 

It also makes it clear that occasional attendance at qualifying premises is to be considered in determining if the capacity threshold is met.  For instance, a store may have a maximum safe occupancy rate (based on its fire safety assessment) of 300, but historic records show there are usually well below 200 individual – including staff – on the premises at the same time.

Those responsible for the shop therefore initially consider the shop to be out of scope of the Act. However, records also show that over the last three years the number of individuals on the premises at the same time has reached 300 individuals – including staff – on several occasions during Black Friday and January sales. This means that while the average number of individuals on the premises at the same time is below 200, it is reasonable to expect that 200 or more individuals will be present on the premises at the same time, from time to time. The store should be reassessed as in scope of the standard tier.

For qualifying events, capacity is an assessment of the highest number of attendees at any point during the event.

The steps to be taken by responsible persons will depend on the size and nature of the activities at qualifying premises and qualifying events. For standard duty premises, public protection procedures such as evacuation, invacuation, lockdown and communication procedures must be implemented without necessitating physical alterations or equipment purchases. Enhanced duty premises and qualifying events must put in place and regularly review public protection measures to reduce vulnerability to terrorist acts and minimise the risk of physical harm to individuals. These measures must be documented and submitted to the Security Industry Authority (SIA) – the regulator empowered to monitor the new public protection measures required to be undertaken by qualifying premises and events.

The guidance recommends that public protection procedures are put in place through a set of documented actions, or a plan, that staff can implement rapidly and effectively to reduce the risk of harm to people, including their own staff. Specific consideration should be given to the dissemination of public protection procedures at unstaffed premises, perhaps by displaying procedures in communal areas via posters.

All staff should be made aware of the procedures, understand them and how to implement them in the event of an attack. This is likely to involve some form of training.

The guidance emphasises that whatever the measures adopted by a responsible person, they should be proportionate to the circumstances. This means, for example, that whilst there is no statutory requirement in the Act to make any physical alterations or to purchase specific equipment relating to putting public protection procedures in place, it may be that in certain circumstances it is reasonably practicable to do so. Risk assessment will be critical.

Commenting on the new guidance, Kevin Bridges, health, safety and fire law expert at Pinsent Masons, said: “The guidance is long and detailed with helpful illustrative scenarios and additional non- statutory guidance on some areas. The emphasis on proportionate procedures will also be welcomed, particularly by smaller premises concerned at the potential extra cost of the new duties. This includes clarification that there is no requirement to engage third party products or services to comply with the Acts requirements.”

Bridges said that the detailed guidance should be carefully considered by responsible persons as they seek to comply with the significant new duties imposed upon them in advance of the likely start date of April 2027. 

The Home Office has also published three non-statutory supplementary documents intended to provide further supporting information in relation to the guidance. These suggest methods for calculating the reasonably expected capacity and outline further illustrative examples of in and out of scope qualifying premises and events. Supplementary document C outlines existing training and awareness products that could be useful to responsible persons.

Jon Cowlan, a health and safety expert with Pinsent Masons, said the guidance provided helpful, scenario-based examples that would be useful for businesses in determining in-scope premises and qualifying events, and when assessing attendance numbers and the steps to be taken to meet the legislation’s requirements.

The Security Industry Authority (SIA) has also launched a public consultation on how it intends to oversees and support businesses comply with the new Act. It is inviting the public to respond to the consultation by 12 June.

Cowlan said the consultation would help inform the SIA’s enforcement approach: “The consultation will enable potential responsible persons to raise concerns they may have and fully understand the SIA position on what to expect regarding its approach.”