Graffiti on run down estate garage

+ Evidence shows that careful design of buildings and surrounding space can reduce crime.

Whose job is it to prevent crime? The police? The courts? Certainly. However, I’d argue that crime prevention is also the responsibility of planners, architects, developers and managers of public space. And they can use simple evidence-based design measures to do it. 

Crime prevention through environmental design (CPTED) is an approach that reduces crime through the design and manipulation of the built (and sometimes the natural) environment. This doesn’t mean fortification – locks, bolts, high walls, fences and barriers – but subtle design changes, ideally at the pre-planning stage.

Natural surveillance is one such design change. By ensuring that properties face the street and that sightlines are clear of overgrown trees, high walls and fences, you remove hidden-from-view areas where crime could be committed unseen.

This is one of the five overarching principles of CPTED, which are:
1. Physical security – securing buildings and spaces to an appropriate level
2. Surveillance – allowing both formal and informal surveillance by users of a space, creating a feeling of unease amongst non-legitimate users
3. Movement control – limiting access, exit and through movement
4. Management and maintenance – creating a positive image and ensuring that future maintenance is easy
5. Defensible space – a clearly defined ownership, purpose and role enhances feelings of territoriality amongst residents and legitimate users.

Does this approach really work? In the UK, these principles underpin the police-led award scheme Secured by Design (SBD). Evaluations of the scheme, including one on which I worked in 2011, have shown that it does.

We found that non-SBD properties in West Yorkshire experienced a burglary rate of 22.7 per 1,000 dwellings. This compared to just 5.8 per 1,000 for the sample of properties where Secured by Design principles had been applied.

The impact of individual measures can be striking. For example, we found that properties overlooked by between three and five other properties experienced 38% less crime than those not overlooked.

Crime can ruin lives, but it also carries a significant financial cost – so reducing crime saves money. In fact, it’s been calculated that implementing Secured by Design pays for itself in two years, and that’s only taking into account costs associated with burglary and criminal damage.

This is why the benefits of CPTED are being recognised globally. In New South Wales, Australia, developments the local council considers pose a crime risk must have a crime risk assessment. And The Netherlands has one of the most comprehensive approaches to embedding CPTED within the planning process.

This just scratches the surface. In my book, I detail a vast amount of research that illustrates the effectiveness of CPTED. So surely our duty as planners, designers, architects, builders, police and researchers is to use this evidence to ensure that housing everywhere is built with CPTED principles in mind.

Given the evidence, can you think of a reason why designers, architects, and planners shouldn't design buildings with crime prevention in mind?