James Q Wilson: Author of the 'broken windows' approach to crime

James Quinn Wilson, who has died at the age of 80, was a quietly spoken conservative scholar in the fields of political science and social science who, in the eyes of his admirers, left a lasting mark on the face of America.

He did so through a single phrase – "broken windows" – which has been described as launching a revolutionin law enforcement. It is credited by many with reducing crime and thus bringing major improvements in several major US cities. Wilson's most avid enthusiasts claim the simple concept saved thousands of lives by pointing policing in a new and community-oriented direction.

The theory, sometimes referred to as zero tolerance, was simple enough: that police should not confine themselves to major offences but should also focus on the quality of life. If people were permitted to hang around on a street corner drinking, being abusive to others or playing truant, Wilson contended, then it was virtually certain that burglaries, car thefts and assaults would increase. Similarly, drug-dealing, prostitution and even public drunkenness and graffiti could drag a district down. This in turn could lead to the inevitable deterioration of a neighbourhood with a gradual exodus of its more law-abiding residents.

As Wilson and a colleague put it in a seminal 1982 article: "One unrepaired broken window is a signal that no one cares, and so breaking more windows costs nothing." It was the theory of the thin end of the wedge, the argument that a stitch in time could save nine.

He was a far-ranging thinker, producing almost a score of books and countless articles on subjects which included politics, personal character, race and marriage. He co-authored American Government, a standard textbook in use in colleges and high schools.

During his long life he was showered with awards, receiving the Presidential Medal of Freedom from George W Bush and serving as advisor to Presidents Johnson, Nixon and Reagan.

When Nixon was in power one of his senior aides famously introduced Wilson to him with the words: "Mr President, James Q Wilson is the smartest man in the United States. The president of the United States should pay attention to what he has to say."

Labelled a neoconservative, Wilson was a Republican who none the less said he voted for Democrats Johnson and Kennedy and worked in Hubert Humphrey's presidential campaign. The son of a salesman, he was born in Denver and brought up in Long Beach, California. He studied in California, recounting, "I was the first member of my family for as many generations as I could count who went to college."

He then spent three years in the navy during the Korean war before going on to take advanced degrees at the University of Chicago. He spent the years from 1961 to 1987 at Harvard teaching, writing and serving on a number of national commissions concerned with topics such as crime, drug abuse, delinquency and foreign intelligence.

Despite his long years at Harvard he was not a natural fit as a conservative in a generally liberal institution. A right-wing admirer proclaimed proudly: "For many years he told the truth and taught the truth against the liberal tide at major American universities and venues around the world."

Although he was trained as a political scientist he wrote, he said, about things which seemed important about which no one had said much. He listed among his themes "blacks in city government, reformers in local politics, the causes of crime and new ways to deal with it, the differences between strong and weak families, and the origins of our moral sense."

He was noted for the particular clarity of his writing style, which he attributed to the advice of one of his professors. "He told me that if I ever learned to write clear English I might amount to something," Wilson recalled. "He said, 'Stop writing what you think is social science.'"

A colleague commended his "encyclopaedic command of data, incisive mind, great modesty and gentle humour," while a friend said: "He spoke vividly, precisely and concisely with deeply insightful observation."

The broken windows theory really came to the fore when it was enthusiastically taken up by the New York mayor Rudy Giuliani. To put it into effect Giuliani appointed a new police commissioner, William Bratton of Boston. Their approach led to a distinct drop in crime, in particular violent offences, though some have suggested this may also have been due to factors such as the ending of a crack cocaine epidemic and an overall fall in the numbers of young males.

Bratton went on to head the police department in Los Angeles, where a similar improvement took place. Last year he indicated he was interested in the job of Commissioner of the London Metropolitan Police, but did not secure the appointment despite reports that David Cameron saw him as a possible contender.

In a tribute to Wilson, Bratton said: "He reshaped the way law enforcement thought about its role and staunchly defended the idea of proactive policing that focuses not only on preventing crime but disorder."

James Quentin Wilson, political scientist and crime theorist: born Denver, Colorado 27 May 1931; married 1942 Roberta (one son, one daughter); died Boston 2 March 2012.