Measure type: Deflection

From Securipedia
(Redirected from Measure: Deflection)
Jump to navigation Jump to search

Deflection is the measure of reducing risk by creating circumstances that direct criminals to less critical objects or redirects the motivational causes into non-criminal means of expression.


wall dedicated for graffiti in Barcelona
A fly drawn in a urinal, a deflection measure to prevent visitors from aiming at other 'targets'

This is the channelling of potentially criminal or aggressive behaviour in more pro-social directions by means of architectural, equipment, and related alterations.


  • Provision of graffiti boards and mural programs where graffiti artist may legally express themselves
  • Interesting wallpaper, daily newspaper, chalkboard on bathroom wall
  • Providing activity centres, sport halls or skateboard terrains for potentially loitering youth
  • Separating incompatible public by designing some areas to appeal to only one group and other areas to the other group


Security issues where this measure can be effective and influenced by the urban planner, are:

Financial gain Boredom or compulsive behaviour Impulse Conflict in beliefs
Burglary Physical assault Destruction by riots Mass killing
Ram-raiding Sexual assault Destruction of property by fanatics
Pickpocketing Vandalism
Robbery Graffiti
Raid Antisocial Behaviour
Vehicle theft


General considerations

As this measure does not actually reduce crime, but rather directs the crime to less critical targets, the measure is best suited for crimes that are (more or less) acceptable in specific places, such as vandalism or graffiti. For more serious crimes that would be unacceptable in any circumstance, this measure is not applicable.

Urban planning considerations

The use of deflection methods encourages responsible use of urban spaces by providing a suitable outlet for activities which would otherwise take place in an anti-social manner. Deflection is becoming an important tool for urban planners, enabling them to facilitate the protection of urban spaces which would otherwise be the target of criminal or anti-social activities. From a planning perspective, it is important to ensure that facilities which are designed to accommodate deflection are seen as a more attractive option than those that would otherwise be used.

Safety/security considerations

Before redirecting crime to another target one should be well aware of the possible consequences for that new target and its surroundings. For example, opening a skateboard park to get rid of loitering youth can cause inconvenience at the skateboard park due to the noise of rolling skateboards, an increase of vandalism in the surroundings or harassments in the bus to and from the skateboard park.

Social considerations

Deflection may result in displacing risk and hazard from one urban area to another. The measure should be assessed in the broader context of the public interest. While the public interest is a question of continuous debate, both in its general principles and case-by-case applications, it requires a conscientiously held view of the policies and actions that best serve the entire community. An important social aspect is the responsiveness of the measure of deflection to citizens' felt security needs. Measures will only be responsive if they are based on identification of citizens’ self-perceptions of vulnerability and resilience as well as their relation to/interaction with resilience-enhancing measures centred on built infrastructure.

Deflecting risk is no substitute for continuously informing citizens of risks, how to assess risks, and how to prepare for risks. [1]

Practical addressing of social aspects and aspects of security culture as they relate to the measure of deflection can best be accomplished by appropriately involving citizens, based on a set of introduced methods of citizen participation as compiled by VITRUV. Ideally, planning for the measure of deflection should include tests of usability in relevant social contexts. A suitable method is for example appreciative planning that helps work out shared and consensual perspectives on security aspects in the urban planning.

Economic considerations

From a rational-economic perspective, the deflection of potentially criminal or aggressive behaviour in more pro-social directions will (in a positive way) shake up the risk-benefit analysis of a (potential) criminal whether or not to commit a crime. Put differently, it will make the next best alternative more attractive compared to the intended criminal act, increasing its opportunity cost. This process of deterring and preventing a criminal act leads to a reduction in crime, and automatically also of the negative economic impact of crime. The provision of 'graffiti boards' (where messages can legally be painted), for example, will not just prevent material and immaterial damage to other urban objects, but will also prevent indirect economic damage to the economy, as it contributes to a safe and whole environment, attracting investors, tourists, richer citizens, etc.

Deflection mitigates the chance of a security threat, but at the same time demands some kind of investment in time, capital and effort by private agents, companies/developers and the public authorities. The cost of deflection contains the relatively straightforward direct expenditures on capital equipment and operational cost (both temporary and permanent) such as investments and investments in activity centres, sport halls or graffiti boards. In addition, deflection measures generate various types of secondary effects due to its effect on society. If this will happen, depends, amongst others, on the impact of these measures on the perceived security of citizens and investors, or if the measures influence the reachability of an area.

In order to decide if this specific security measure makes sense from an economic point of view, the urban planner should not just map both the cost and benefits of deflection measures (both direct and indirect), but also wonder if there exist potential alternative security measures that have a better value for money (benefit-cost ratio)[2]. On top of that, one should always consider how stakeholders (citizens, suppliers, customers, employees, etc.) are affected by the considered measures, and to which extend. Will the foreseen deflection measures, for example, have a long-lasting effect, or will they only help for a short period of time? Or, will the deflection measures lead to crime displacement? Economic tools such as the social cost-benefit analysis (first question) and economic impact study (second question) can help decision makers to answer these questions and to prevent wasteful expenditures on security. In terms of benefit-cost ratio, deflection can be considered as a type of security measure which in a relatively subtle way increases security, in contrast to measures such as security guards, big concrete walls and barb wire that may be pervasive, but can also arouse feelings of fear and anxiety[3].

Mobility considerations

The road network can be designed in such a way that areas where visiting people or vehicles are not wanted will attract less traffic, for example by making the roads to these areas less attractive (lower speed limit, speed bumps etc.). Or, the other way around, by providing good and easily accessible roads between the origin/destination pairs that have to accommodate a lot of traffic. Also green waves (successive intersections where the green times are tuned such that drivers will experience successive green traffic lights on their route) can be established on these roads, while larger red times on intersections can be used to make other routes less attractive.

Ethics considerations

Deflection may come with ethics issues of distributive justice, such as risks of reifying uneven distribution of security in society. Architectural alterations to support deflection can contribute to selective delivery of security, making some groups of citizens more secure, and other groups of citizens more vulnerable. This may be, for example, the case in a situation where deflection in some area displaces crime to another community. This illustrates the need to provide norms and standards beyond frameworks for built infrastructure

In general, pinpointing specific ethics aspects in resilience-enhancing measures needs to consider, among other things, citizen security cultures and citizens' personal concerns. There are no ethics considerations that can be planned or implemented without prior identification and addressing of citizens' perceptions. To support this, VITRUV offers a commented list of methods to determine ethics aspects in relevant urban planning.

Legal considerations

Legal considerations when considering deflection measures are:

Footnotes and references

  1. Dennis S. Mileti/John H. Sorensen: Communication of Emergency Public Warnings. A Social Science Perspective and State-of-the-Art Assessment. Oak Ridge, TN: Oak Ridge National Laboratory, U.S. Department of Energy, 1990.
  2. See also the flow chart of an economic assessment.
  3. Coaffee, J., P. O’Hare, and M. Hawkesworth (2009): The Visibility of (In)security: The Aesthetics of Planning Urban Defences Against Terrorism. Security Dialogue 2009 40:489.