The broken windows theory is not only one of the most known and discussed theories in behavioural psychology, it’s also of great value to architects and designers. This is because it concerns the environment in which we live and its ability to influence human behaviour. A subject that plays a central role in any design activity, but despite advances in research, we still don’t know enough because it’s linked to one of the most mysterious objects in the universe: the human brain.
Philip Zimbardo’s experiment
The history of the Broken Windows Theory begins in 1969 when Philip Zimbardo, a professor of psychology at Stanford University, conducts a social experiment to observe human behaviour in public spaces.
Zimbardo “abandons” a car on a street in the Bronx in New York and in a residential neighbourhood in Palo Alto, California. Two diametrically opposed socio-economic contexts in which his research group hides to record the behaviour of citizens at the abandoned car.
It takes ten minutes for the Bronx’s car to be vandalised by a family of three who removes the battery and radiator. Within 24 hours, the car has already lost all its valuable parts and is at the mercy of the vandals who destroy the glasses and bodywork. It’s here that Zimbardo makes a first unexpected observation. Most of those who vandalised the car doesn’t fit the classic definition of thugs but are well-dressed people from whom one wouldn’t expect anti-social behaviour.
Meanwhile, in Palo Alto, the car is still intact. After a week, no one has vandalised it or tried to remove valuable parts. So Zimbardo decides to break a car window. This particular detail is enough for what has already happened in the Bronx to also happen in Palo Alto. Within hours, the car is attacked and vandalised, quickly becoming a scrap. Once again, the researchers observe the vandals are apparently respectable people who only needed a smashed car window to break the law.
The broken windows theory by Wilson and Kelling
Zimbardo’s experiments spark an important debate in the research community. This includes James Q. Wilson and George Kelling, who in 1982 published their article on the broken windows theory. According to the authors, vandalism can occur anywhere, regardless of the social context. All it takes to affect the common barriers of mutual respect and civility obligations is a signal of neglect and disinterest.
In an infamous context where cars are abandoned and things are frequently stolen or vandalised, even people who’d normally never think of vandalising a car could to do it. In Palo Alto, in a more comfortable environment where the norm is to play by the rules of law, a broken window is enough to start the vandalism: it’s the signal that nobody cares.
A broken window in an abandoned car conveys a sense of decay, of disinterest, of carelessness, a sense of breaking the codes of coexistence, of the absence of norms, of rules. Negative values characteristic of neighbourhoods where crime is highest and where neglect, dirt, disorder and abuse are most common.
The Application of the Broken Window Theory in New York City
In 94, a few months after his election as mayor of New York, Rudolph Giuliani announces “zero tolerance”, a policy based on the theory of broken windows and on tightening police measures against petty crimes such as littering, graffiti and minor vandalism. In a few months, New York City’s municipality will begin a major cleaning campaign, painting and restoring public furnishings, walls and floors, in keeping with the motto “a cleaner city is a safer city”.
As the city’s crime rate drops several points, Giuliani gives credit to his zero-tolerance policy and advocates its spread, despite much criticism from the public and researchers.
Architecture and the broken windows theory
Regardless of the success and legitimacy of its application in New York, the broken windows theory is of great value to architecture and design. Not only because it confirms how the space we live in influences our behaviour, but also because it signals how great that influence is. If a broken window is enough to signal carelessness and lack of attention leading to vandalism, how much of what we do results directly from the spaces and architectures we dwell on every day?
- Zimbardo, P.G., 1969. The human choice: Individuation, reason, and order versus deindividuation, impulse, and chaos. In Nebraska symposium on motivation. University of Nebraska Press.
- Wilson, J.Q. and Kelling, G.L., 1982. Broken windows. Atlantic monthly, 249(3), pp.29-38.