The broken windows theory states that visible signs of disorder and misbehavior in an environment encourage further disorder and misbehavior, leading to serious crimes. The principle was developed to explain the decay of neighborhoods, but it is often applied to work and educational environments.
Although widely used to explain criminal behavior and to inform policing policies in the 1990s, psychological and scientific evidence backing the theory is scarce. As a result, it has been increasingly discredited.
The concept, defined in 1982 by social scientists James Wilson and George Kelling, drawing on earlier research by Stanford University psychologist, Philip Zimbardo, argues that no matter how rich or poor a neighborhood, one broken window would soon lead to all the windows being broken: “One unrepaired broken window is a signal that no one cares, and so breaking more windows costs nothing.” Disorder increases levels of fear among citizens which leads them to withdraw from the community and decrease participation in informal social control.
The theory was put forth at a time when crime rates were soaring, and it often spurred politicians to advocate policies for increasing policing of petty crimes—fare evasion, public drinking, or graffiti—as a way to prevent, and decrease, major crimes including violence. The theory was notably implemented and popularized by New York City mayor Rudolf Giuliani and his police commissioner, William Bratton.
In research reported in 200, Kelling claimed that broken-windows policing had prevented over 60,000 violent crimes between 1989 and 1998 in New York City.