Security issue: Destruction by riots

Destruction by riots is the act of vandalism of property by groups for a shared rational or rationalised reason.

Description
Riots are physical expressions of discontent by large, mostly unorganised groups of people, expressed in vandalism, assault and/or pillaging. Although the riot may be unorganised, the reason for these people being there may well have a collectively shared motivation. Based on their nascency, three types of riots can be distinguished:

Organised protests
Sometimes peaceful, organised protests can quickly turn into unorganised and destructive riots. Examples of such events are the 2011 events in Tottenham, London and the riots in Rome in October 2011. In these cases the protest, especially when arousing stormy emotions, can turn into a riot when external circumstances provoke strong and emotional responses.

Events
Events which arouse strong emotions, especially when aggravated by a strong sense of competition or the use of alcohol, can disinhibit natural restraint and lead to group processes that can lead to excessive violence. The sport of football has a long history of riots associated with it. These kinds of riots are often associated with a group of agitators, known as hooligans, who instigate such violent actions.

Social unrest
Felt social wrongs can build a common frustration that can release itself in sometimes very violent and wide-spread riots. The 2005 Paris civil unrest, which resulted in a three-month declaration of the state of emergency.

Contributing circumstances
Known circumstances to influence the likelihood or effect of destruction by riots, are presented in the table below:

Social impact
Destruction by riots can have social impact such as increase in citizens' perception of insecurity, fear of crime, and avoiding of the places of the riots. This can result in urban space becoming increasingly more attractive for rioters, with a chain of increasing destruction.

Economic impact
Riots lead to considerable costs in both a direct (primary) and a indirect (secondary) way. Direct costs of destruction by riots come in the form of:
 * Preventive costs in anticipation of riots (e.g. security measures, insurance);
 * Material and immaterial costs as a consequence of rioting (e.g. physical damage, repairs, medical costs, mental harm) ; and
 * Responsive costs to riots (e.g. the costs of detection and prevention, prosecution, support trial, etc.).

In addition, the secondary economic impact of crime has to be considered:
 * Riots make investors nervous: "Although the Thai stock market has recovered strongly this year, investors saw a 10% drop while the rioting was going on (in 2010) . "Moreover, while Thailand no doubt benefited from its reputation as a peaceful and relatively orderly country, countries with chronic troubles risk getting labelled as "basket cases" and virtually eliminated from serious consideration as investment destinations".
 * Rioting also has a distinct impact on tourism. "China reported that disturbances in Xinjiang in 2009 led almost 85,000 travellers to cancel trips to the area, while Thailand has seen a big drop in tourism since its political troubles turned violent" in the spring of 2010.

In theory, security measures can prevent destruction by riots, but not without costs. Target hardening or access control, for example, is costly and there is always the risk of crime displacement. Crime is closely related to poverty, social exclusion, wage and income inequality, cultural and family background, level of education and other economic and social factors. With the help of economic tools such as social cost-benefit analysis it is possible to overview the costs and future benefits of security measures in order to decide which types of measures are best suited for a specific urban planning situation.

Mobility impact
Since riots take place at Open and civic spaces, the mobility function of those areas might be seriously hampered. Accessibility might be reduced when, for example, roads are blocked. Also safety of vulnerable road users might be reduced, especially when important bicycle lanes or pedestrian paths are crossing the riot location.

With traffic management measures one can attempt to concentrate the riot at a location with little impact on mobility and to reduce the negative consequences for mobility, for example by rerouting traffic around the riot location.

Access control can ensure only flows of the intended people enter or exit the area and can enforce and intended separation of crowds.

Also by directing traffic flows (including flows of people), the crowd and traffic flows can be controlled.

Safety impact
Riots can do massive physical and/or bodily damage, as shown by the examples above. A rioting crowd has very little attention for the consequences of their actions. This is why one of the first measures taken if a riot is already broken out, is to isolate it to limit the damage.

Measures
Potential measures that can mitigate the likelihood or impact of destruction by riots include:


 * Target hardening to ensure violence cannot overcome other measures taken (such as directing traffic flows or access control), can prevent a riot getting out of hand.
 * Surveillance may have some effect on deindividuation if spectators know they are there.
 * Intervention force is needed to make detection measures, such as alarms or surveillance, effective.
 * Directing traffic flows can be effective in reducing the chance for potential rioter to approach vulnerable areas or opponents. By providing clear and logical access and exit routes and/or transportation through an area, unnecessary provocation can be avoided. Also one could consider levels of permeability if it would facilitate natural crowd dispersion
 * Removing means can contribute to a more secure environment by making sure any materials that might be helpful for riots are unavailable, e.g. by designing a road in asphalt instead of throwable bricks.
 * Avoid long stretches of blank walls where the space is located near a public throughway. Where this cannot be avoided access to buildings / blank walls should be made difficult through the planting of trees, bushes or shrubs.
 * Controlling disinhibitors such as alcohol can directly decrease the problem. A careful design with compatible land uses and activities is important.
 * Removal of crime motivator can sometimes be effected by moving a riot-prone activity to a less vulnerable area.
 * Access control can ensure only flows of the intended people enter or exit the area and can enforce and intended separation of crowds.
 * Screening can sometimes be applied (for examples at stadiums at high-risk matches) to ensure the nature of the visitors, such as scanning for a restraining order or for the presence of forbidden materials, such as fireworks or weapons.