Setting standards for properties to improve physical security and lower the risk of crime.
This summary is part of the Crime Reduction Toolkit, which presents the best available research evidence on what works to reduce crime.
Focus of the intervention
Secured by Design (SBD) is a UK police initiative that aims to reduce crime by improving the security of buildings. Established in 1989, it encourages developers to build properties to specific security standards. The principles of SBD are based on situational crime prevention (focusing on the settings where crime occurs) and crime prevention through environmental design. Buildings that meet these standards are awarded SBD status.
The SBD specifications cover urban design and the physical security of the built environment, including doors, windows, fences and lighting. Developers work with police Designing Out Crime Officers (DOCOs) to achieve SBD accreditation and ensure that housing developments are built to specified standards. Three levels of accreditation are available, depending on the level of compliance with these standards – gold, silver and bronze.
What research is this summary based on?
This Crime Reduction Toolkit summary is based on the findings of one meta-analytic review covering nine studies.
These assessed whether properties meeting SBD standards experienced less crime than properties not meeting SBD standards. The sample of nine studies included studies on new properties meeting SBD standards (n=7), and studies of existing properties refurbished to meet SBD standards (n=2). The outcomes covered by the review included burglary, attempted burglary, vehicle crime and all crime types.
All the studies included in the review were from the UK.
Effect – how effective is it?
- The research suggests that Secured by Design has reduced crime overall.
In general, pooling evidence across all nine studies included in the review, burglary in properties meeting SBD standards was 53% lower than in properties not meeting these standards. Eight of the nine included studies reported a decrease in burglary, with the decrease being statistically significant in three of these studies. Only one study reported an increase in burglary, however, this finding was not statistically significant.
Sub-group analysis
Due to substantial variability in the primary studies, the review undertook subgroup analysis of studies focusing on different types of property, crime types and study designs. Statistically significant effects were found in four subgroups of studies.
- new builds: In studies comparing new build properties meeting SBD standards with new build properties not meeting these standards (n=6), burglary was 65% lower in SBD properties
- attempted burglary: In studies focusing on attempted burglary only (n=3), attempted burglary was 77% lower in SBD properties compared to non-SBD properties
- post-intervention designs: In studies with a post-intervention design which matched treatment and control groups (n=7), SBD was associated with a 65% reduction in burglary
- matched pairs designs: In studies with a matched pairs design combining police recorded data with victimisation survey data (n=7), SBD was associated with a 65% reduction in burglary
The review also found reductions in crime in studies focusing on vehicle crime (n=4) and all crime types (n=3). However, the reductions in these studies were not statistically significant.
How robust is the review evidence?
- The quality of review methods used to assess the impact of SBD was very strong.
The review was sufficiently systematic that most forms of bias that could influence the study conclusions can be ruled out. The evidence is taken from a systematic review which demonstrated a high-quality design in terms of its use of a transparent and well-designed search strategy, calculation of appropriate effect sizes, assessment of heterogeneity, use of appropriate weighting and assessment of publication bias.
However, the review noted several limitations with the primary studies. Only two of the review’s primary studies focused on existing properties refurbished to SBD standards. Out of the nine eligible studies included in the review, three were over 20 years old and may have been superseded by developments in housing and SBD standards, as well as policy, technology, building materials and criminal tactics. Further limitations highlighted by the review included poor methodological quality among some of the primary studies, lack of statistical power when comparing levels of crime in treatment and control groups, and lack of attention to the quality of SBD standards.
Mechanism – how does it work?
- The quality of review methods used to assess how SBD works was low.
SBD is assumed to reduce crime by increasing household security, removing opportunities to commit burglary and other offences. For example, physical security measures such as increased lighting may deter burglary by increasing the chances of detection, or increasing the effort involved in committing it (target hardening). The review noted that weak security has been identified as a consistent risk factor for burglary victimisation, while interviewed offenders have identified good security measures as a deterrent for burglary.
The review did not test these assumptions, as the primary studies provided insufficient information to do so.
Moderators – in which contexts does it work best?
The review provided insufficient information to assess where, when and for whom SBD might work best.
Implementation – what can be said about implementing this initiative?
The review provided insufficient information to assess how to implement SBD. The review gave no account of how SBD was implemented, or any implementation challenges encountered by the primary studies.
Economic considerations – how much might it cost?
The review provided insufficient information to assess how much SBD costs. The review did not mention the costs or benefits of SBD, and no formal economic analysis was provided.
General considerations
- Three of the nine included studies were over 20 years old, meaning that there is a risk that the housing and SBD standards they analysed have been overtaken by more recent developments.
- Greater attention is needed on the quality of SBD standards themselves, and variation in the implementation of these standards.
- Further research is needed on the mechanisms by which SBD influences crime outcomes and the contexts in which SBD might work best.
Summary
- The research suggests that SBD has reduced crime overall.
Burglary in properties meeting SBD standards was 53% lower than in properties not meeting these standards. The most significant reductions were found in studies focusing on new build properties, where SBD standards were associated with a 65% reduction in burglary compared to properties not meeting these standards. Attempted burglary was also 77% lower in SBD properties compared to non-SBD properties.
Further research is needed on the mechanisms by which SBD reduces crime as well as the conditions in which SBD works best.
Reviews
Review one
Reference
Armitage R, Sidebottom A and Tompson L. 2024. ‘Reducing burglary through Secured by Design: A meta-analysis’. University of Huddersfield, UCL Jill Dando Institute of Security and Crime Science and New Zealand Institute for Security and Crime Science, University of Waitako.
Additional resources
Related Crime Reduction Toolkit summaries
Other Crime Reduction Toolkit summaries of relevance to Secured by Design include: