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Zimbardo Illustration

Broken windows theory derived from a cluster of experiments conducted in the early seventies. One experiment in particular played a significant role in shaping the theoretical framework of broken windows theory. In 1969, Stanford psychologist Phillip Zimbardo conducted a famous criminological experiment showcasing the significance of “broken windows” symbolism. Zimbardo intentionally left an abandoned car in a neighborhood in Bronx, New York. To evaluate whether or not any passerby would tamper with or vandalize the vehicle, Zimbardo removed the license plates from the car and left the hood open. In the Bronx, the car almost immediately attracted the attention of vandals and thieves. Zimbardo explained that bystanders stripped the car of all its valuable parts and contents within 48 hours.[1] The most remarkable feature of Zimbardo’s study highlighted the aftermath of recreational violence that wandering offenders decided to inflict on the discarded car. In “Crime: A Diary of a Vandalized Car”, Time reporters recounted the damaging effects of “miscreants” who encountered the vehicle on the street.

“By the end of the first 26 hours, a steady parade of vandals had removed the battery, radiator, air cleaner, radio antenna, windshield wipers, right-hand-side chrome strip, hubcaps, a set of jumper cables, a gas can, a can of car wax, and the left rear tire…Nine hours later, random destruction began when two laughing teen-agers tore off the rearview mirror and began throwing it at the headlights and front windshield…Eventually five eight-year-olds claimed the car as their private playground, crawling in and out of it and smashing the windows.”[2]        

Zimbardo’s findings illustrated that when the physical act of vandalism (i.e. breaking windows) combined with environmental conditions where neglect and abandonment remain visibly prevalent, individuals are much more likely to engage in self-serving and destructive criminal behaviors. Moreover, the optics of broken windows theory invites criminal offenders (especially young people) to take advantage of the lack of social controls and participate in seemingly low-risk criminal activities.

Like Zimbardo, print media utilized the “broken window” trope to illustrate the rise of disorder in American cities. Specifically, editorials covering incidents of police-citizen rivalry in the 1970s relied on the imagery of disorderly black youth and “broken windows” to underscore the need for order maintenance policing practices. For example, in East Los Angeles on August 10th, 1971, local residents belonging to “rival car clubs and gangs” broke out in “bloody fistfights.”[3] LA Times journalists wrote: “Both Negroes and Mexican-Americans were involved in the Riverside violence…Horns honked, motors roared, youths yelled at one another, more fights flared—and then, about 11pm, a store window shattered.”[4] In this depiction, a “broken window” encapsulated the chaotic imagery of social dysfunction and civil disorder in East L.A. The Los Angeles reporters specifically emphasized the significance of that “broken window” in the following quote from a 17-year-old bystander: “I heard a window break…and it was as though it triggered everything. There was one window, then another.”[5] As the popularity of order maintenance policing practices intensified throughout the seventies, broken windows emerged as a dominant symbol of disorder. Furthermore, the article’s vignettes of “smashed’ plate-glass windows” and “rampaging…black youths” sensationalized and spotlighted minorities as the primary “troublemakers” and offenders of public order.[6]

In the aftermath of the urban disturbances in areas like Brooklyn,[7] Harlem,[8] and Washington D.C.,[9] academic studies on crime and policing garnered immense political traction among policymakers and law enforcement practitioners. As media coverage of violent window smashing and urban uprisings continued, George Kelling became intrigued by Zimbardo’s “Diary of a Vandalized Car” study. Inspired by Zimbardo’s work, Kelling developed a study focused on the role of policing in patrolling incidents of disorder, such as auto vandalism and theft on the street. During his tenure as the Director of Evaluation at the Police Foundation, Kelling became the lead author of one of the most celebrated policing experiments of the century—the Kansas City Preventive Patrol Experiment.[10]

[1] Zimbardo, Phillip G. Anonymity of Place Stimulates Destructive Vandalism. Accessed December 05, 2016.

[2] "Crime: Diary of a Vandalized Car." Time. February 28, 1969. Accessed December 05, 2016.,9171,988151,00.html.

[3] Mosqueda, John, and DIAL TORGERSON. 1971. Police, deputies restore order in riverside, east L.A. areas. Los Angeles Times (1923-Current File), Aug 10, 1971. (accessed November 29, 2016).

[4] Ibid.

[5] Ibid.

[6] Ibid.

[7] In July 1971, groups of youth threw stones and bottles as police officers at the Sunset Park section of Brooklyn. One police officer suffered lacerations and police officers arrested at least five persons for the disturbances. Previous disturbances erupted on a few days prior to this incident. Demonstrators from the predominately Puerto Rican neighborhood area set fires and damaged police and fire cars along local streets in Brooklyn. To read full newspaper clipping see: POLICEMAN INJURED, 5 SEIZED IN MELEE. 1971. New York Times (1923-Current file), Jul 30, 1971. (accessed December 6, 2016).

[8] In June 1970, The Young Lords, dubbed by media as a “militant Puerto Rican youth organization”, called a rally in East Harlem at 6pm in protest of the recent arrest of the Young Lords’ finance minister, 16-year-old Juan C. Ortiz. Following the rally, hundred of youth smashed windows, set fires, damaged shops, destroyed cars, and pelted policeman with bottles and rocks. A dozen fireman and seven police officers reported injuries from protestors. To read full newspaper clipping see: By, ROBERT D. 1970. Hundreds in east harlem rampage. New York Times (1923-Current file), Jun 15, 1970. (accessed December 6, 2016).

[9] In April 1972, D.C. police told reporters that in parts of Northwest and Southwest Washington police and fireman have increasingly encountered rock-throwing youths.

Three police cars suffered $435 worth of damage while trying to assist a young man suffering from a bleeding gash. Officers explained that a number of police cars have had windshields broken by rocks during the past year. In response, Lieutenant Robert F. DeMilt circulated a memo to citizens and civic groups regarding the increased youth violence within the city. To read full newspaper clipping see: By Alfred E Lewis Washington Post, Staff Writer. 1972. 6th district teen-agers stone police. The Washington Post, Times Herald (1959-1973), Apr 28, 1972. (accessed December 6, 2016).

[10] Kelling, George L., Tony Pate, Duane Dieckman, and Charles E. Brown. The Kansas City Preventive Patrol Experiment. Police Foundation Report. Washington, D.C.: Police Foundation, 1974. 1-56. 

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