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The Jack and Lewis Rudin Distinguished Visiting Scholar Program
I thank you for the invitation to speak with you this afternoon and thank Dr. Gerald Lynch for arranging this impressive gathering. I am especially honored to be presenting the inaugural lecture of the Jack and Lewis Rudin Distinguished Visiting Scholar Program. The Rudin family is synonymous with civic commitment to the well-being of New York City. As one who has devoted most of my professional career to the same cause of a better New York, and as one who has respected the Rudins for their unwavering love of this city, this is a singular honor.
My topic this afternoon is "Declining Crime and Our National Research Agenda: New Yorker's View." This is a serious topic at the intersection of research and policy. I had originally planned to deliver this lecture at Harvard, but after reading in U.S. News and World Report that John Jay College had beaten out Harvard for the distinction of being rated number one among graduate criminal justice policy programs across the country, I thought better of that idea. Seriously, my hope today is to set aside that memorable New Yorker cover of twenty years ago -- the one that shows the world as ending at the Hudson River with a vast wasteland of America stretching to the west -- and look at the issue of crime across the nation through a New Yorker's eyes.
We live in an era of declining crime rates. These declining crime rates are not uniform across the nation, nor across crime types, nor across age groups. Crime rates are declining most steeply in our large cities; yet some medium sized cities are experiencing either stable or rising crime rates. Rates of property crime have been declining fairly steadily for twenty years. Indeed, as Frank Zimring and Gordon Hawkins remind us, the city I was in two weeks ago, Sydney Australia, has a property crime rate quite similar to Los Angeles.
The unique American crime problem is lethal violence, not property crime. Over the same twenty year period, rates of violent crime have shown some volatility, with an increase and decrease in the late 70's and early 80's, then another sharp increase beginning in 1985 and sharp decrease beginning in the early 90's. And, according to the Bureau of Justice Statistics, the decrease in serious violent crime we have experienced over the past several years reflects a sharper decrease among adult offenders than among juvenile offenders.
Yet despite these variations by jurisdiction, crime category and offender age, the overall picture is of historic importance. According to the National Crime Victim Survey, our rates of violent crime are the lowest since the early 70's when the victimization survey was first conducted. And in some cities the numbers are simply staggering. The New York story is particularly compelling. Most in this room will remember 1990, the summer of our despair. Crime seemed out of control; the New York Post headline screamed at the Mayor, "Dave, Do Something." The Citizens Crime Commission called for another 5,000 officers. It was nothing less that a crisis in governance. That summer, Lee Brown, Ray Kelly, Mike Farrell and a small team at the Police Department put together a plan that would increase the police department by 5,000 officers and would begin to unleash the energy, creativity and problem-solving powers of the police under the banner of community policing. In that awful year, there were 2,245 homicides in New York City. Last year, there were 767, a drop of 66 percent. COMPSTAT has become a household word and the New York City Police Department has received well-deserved acclaim for focusing its energies and resources on crime control and prevention.
Yet, despite the best efforts of some effective publicists, we must recognize that this decline in crime rates is not a New York story alone. Indeed, the city experiencing the greatest decline in homicide between 1990 and 1995 (the last year of official records) was not New York City, but Jacksonville, Florida. In fact, two thirds of U.S. cities over 200,000 in population have experienced double digit drops in homicide rates during that five year period.
What is happening with our crime rates?
We all get asked this question. Some of us may even have our pet theories. Some of the explanations offered in the public debate reflect the perspective of the commentator. Police officials here in New York claim that new policing strategies in this City are totally responsible -- but have no insights into declines (or increases) in other cities. Advocates for tougher imprisonment policies point to declining crime rates as vindication for policies that have resulted in a quadrupling of our prison populations over the past twenty years, but can't square that explanation with the results in a city like Boston where deadly juvenile handgun violence has been virtually eliminated without harsher sentencing laws. Some explanations make the crime reduction appear to be the result of laws of mathematics or markets -- that this is merely regression to the mean, or akin to the self-corrections seen in an overheated stock market.
I am particularly struck by the reluctance of the research community to try to understand this phenomenon. At last year's conference of the American Society of Criminology, with one or two exceptions, I could find no plenary session or panel presentation or paper that offered academic perspective on crime's decline. The academic reluctance to engage this important question of crime's decline sometimes approaches disdain for the question itself. When Bill Bratton first asserted that the NYPD was responsible for New York's declining crime rates, prominent researchers scoffed privately that he must be cooking the books, and stated publicly that crime was beyond the influence of the police.
I should not be too harsh on the research community. Research has made important contributions. Our understanding of the rapid increase in violent crime rates in the mid-80's was significantly advanced, in my view, by the development of the "diffusion hypothesis" by Al Blumstein of Carnegie Mellon. He published an article in 1994 showing that, although robbery and burglary rates for juveniles have remained basically the same for twenty years, rates of juvenile violent crime significantly increased beginning in the mid-80's. Between the years 1985 and 1992, the homicide rate for those 18 and younger doubled; during the same period, the number of juvenile homicides with guns also doubled; during that period the arrest rate for nonwhite juveniles for drug offenses also doubled. The Blumstein "diffusion hypothesis" posits that, as crack cocaine hit urban America, established drug markets were destabilized, young people were drawn into the new crack trade, guns were needed to defend turf and to protect street-level operations, and these guns "diffused" into the adolescent culture until they were used to settle traditional adolescent squabbles over coats and girlfriends.
Despite the contributions of this hypothesis to understanding the rise in violent crime, it only begs more questions when considering its decline. Have markets stabilized? where have the guns gone? how are those squabbles being settled now? why are adult rates of violent crime falling more sharply than juvenile rates?
Again, we have some insights from research. The work of Andrew Golub (formerly of John Jay College) and Bruce Johnson on the cycle of the crack epidemic is very important research. Using survey data and urinalysis results from NIJ's Arrestee Drug Abuse Monitoring (ADAM) program (formerly known as the Drug Use Forecasting program), they have shown that the rates at which adolescent arrestees (those aged 18-20) test positive for cocaine (and self-report for crack use) have been declining significantly in some cities, while use rates for older arrestees have declined only slightly. In Manhattan, for example, a slow decline in crack use began in 1989. From 1987 to 1995, the overall rate of detected cocaine/crack use among arrestees hovered around 70 percent and then showed a moderate drop to 62 percent in 1996. However, the rate of crack use among youthful arrestees went from 70 percent in 1988 down to 31 percent in 1991, where it remained through 1995. Then it declined even further to 22 percent in 1996. So we have support for the hypothesis that a younger generation of adolescents is resisting the risky behavior of their elder siblings.
Our knowledge has been significantly enhanced by the recent report by my colleagues at the National Institute of Justice -- our study of homicides in eight cities -- which found a very powerful statistical correlation between the rise and fall of crack cocaine use, as reflected in positive urine tests of arrestees, and the rise and fall of homicide rates. The report also shows increased gun violence resulting in homicide and an increasing rate of homicide victimization among young Black males. In fact, guns accounted for more than 80 percent of homicides in five of the six study sites and Black males, between the ages of 18 and 24, were 24 times more likely to be murdered than would be expected based on their representation in the general population. These research findings, although shocking, help us to better understand our crime problem.
And just last week, NIJ and the White House Office of National Drug Control Policy released a comprehensive study of drug markets titled, "Crack, Powder Cocaine, and Heroin: Drug Purchase and Use Patterns in Six U.S. Cities." New York (or more specifically, Manhattan) was one of the six cities studied in this report. This study showed that, overall, crack cocaine users, when compared to powder cocaine or heroin users, were much more likely to buy their drugs outdoors, to buy them from more than one seller, and to buy them more often. This groundbreaking study -- the first of its kind to compare drug markets across cities and across drugs from the perspective of the drug consumer -- supports the conclusion that crack markets are quite different from other drug markets -- more volatile, more dangerous, and involving many more transactions.
So, we have developed some important insights on crime's rise and decline from research. And I am pleased that NIJ and the Journal of Criminal Law and Criminology will be cosponsoring a symposium on crime's decline later this month at the Northwestern University Law School. Yet I would like to argue this afternoon that we know too little about changing crime rates, and know that too late, and that we should think about designing a much more ambitious research agenda to understand crime in its local context as our challenge for the next century.
I would like to lay the foundation for this argument by talking first about the recent research findings that I think have the greatest significance for shaping the direction of both research and practice. These are drawn from the Project on Human Development in Chicago Neighborhoods which is cofunded by NIJ, with contributions from other federal agencies, and the MacArthur Foundation. This study is a very ambitious, long-term inquiry into the relationship between community, crime, delinquency, family and individual development. At the community level, the Project has surveyed more than 8,700 adult residents in 343 neighborhoods throughout Chicago. In addition, researchers have identified 80 neighborhoods as the focus for a longitudinal cohort study to be conducted over the next eight years. As part of the first wave of this longitudinal study, researchers have conducted interviews with 7,000 children and adolescents and their primary care givers.
This past August, the research team, headed by Dr. Felton Earls of the Harvard School of Public Health, published their first findings in Science magazine. They reported that the largest predictor of violent crime rates was "collective efficacy" -- a term they used to mean a sense of trust, common values, and cohesion in a neighborhood. They found that there are lower rates of violence in neighborhoods that have a strong sense of community and values, where adults are likely to intervene when children are missing from school or scrawling graffiti on building walls. According to Prof. Robert Sampson, a co-author of the report, "cohesion, or efficacy, seems to be a shared vision, a fusion of shared willingness of residents to intervene and social trust, a sense of engagement and ownership of public space." According to Earls, the most important characteristic of "collective efficacy" is a "willingness by residents to intervene in the lives of children." He was referring to a willingness to supervise, or step in, and monitor the children in a neighborhood.
The finding of collective efficacy is important standing alone, but is doubly important when placed in context. Collective efficacy, when assessing predictors of violence, has an impact OVER AND ABOVE traditional predictors such as the racial or ethnic composition of a neighborhood, poverty levels, or residential instability.
These findings have had considerable influence on our thinking within NIJ -- and indeed throughout the Justice Department -- as we are designing an agenda for research and practice.
I will not dwell at length this afternoon on the implications for practice. In sum, our colleagues within different offices of the Department find substantial support in the Chicago research for their efforts to strengthen communities as part of larger crime prevention efforts. A number of comprehensive community programs sponsored by the Clinton Administration -- at least one of which, the Weed and Seed program, predates the Clinton team -- are explicitly premised on the notion that the appropriate role of the federal government is to work with communities to strengthen their infrastructure -- their "collective efficacy" -- as the first order of business in producing safety.
Yet I think the Chicago study's implication for research -- both basic research and applied research -- are quite profound. Let's return to the issue of our crime rates -- first the rise, then the decline. We know very little about how communities were affected by crack's explosive arrival in the mid-80's. Journalistic evidence, anecdotal evidence, and some ethnographic evidence, paint a picture of communities under siege. Having lived in a city besieged by crack -- and working for Police Commissioner Ben Ward and Mayor Ed Koch during crack's onslaught -- I recall vividly the sense we could not hold the line against some awful evil force. I remember distinctly the time in 1984 when Ben returned from a trip to Los Angeles. All was going well at that time -- crime was declining, we had launched the first community policing pilots, Operation Pressure Point had reclaimed the lower East Side from drug dealers, new domestic violence initiatives were underway, it was an optimistic time not too dissimilar to the present -- yet he reported that he had seen a new drug on the West Coast, called "ice" and now called crack, that he said would undo everything we had accomplished if it ever hit New York. It did -- and he was right.
If the "collective efficacy" thesis has validity, we should ask whether those informal social controls weakened during that period, and whether they had a role in the re-emergence of safer communities. There are those who argue that an understanding of the role of community in crime prevention is the missing piece in our research knowledge base. And they argue that the last decade, because of its extreme rise and fall of violent crime, provides the natural setting for understanding those dynamics. Roger Conner, who as a community activist fought to rescue his own neighborhood in Washington, DC from crack dealers, and is now the Executive Director of the Center for the Community Interest, has coined a wonderful phrase for this phenomenon. He says we witnessed the "release of the antibodies" -- that at some point in time, the healthy forces in these devastated communities said they could take it no more, and mustered their collective strength to fight back. George Kelling recently offered a similar explanation for crime's decline in New York City. At his lecture in December, as part of NIJ's series called Perspectives on Crime and Justice, he said that the first healthy sign in New York's return to safety was the organization of community groups -- tenant organizations, business improvement districts, block watchers, safety coalitions -- that fought to restore order, and their efforts were then met by a police department that had been transformed to be more receptive, flexible and effective in responding to crime conditions.
I have my own personal experience with the phenomenon of the "release of the antibodies." When Susan and I lived in New York, we lived in Chelsea. Early in the 1990's, Chelsea suddenly became home to a number of X-rated video stores, peep shows and massage parlors. When Susan drove home one night and saw that a X-rated video store on our block had installed a blinking red light, she said, "We are not going to live in a red light district." She then called neighbors together in our living room, founded the Chelsea Action Coalition, marched in the streets, picketed politicians, and pressed for the adoption of adult use zoning -- which, we are delighted to see, was upheld by the Court of Appeals last week. In a New York Times interview asking why she was spurred into action, she said, "One is an eyesore; but nine is an invasion." The tipping point had been reached -- the antibodies were released.
We find ourselves looking to other disciplines to import theories and models that might shed light on these community dynamics. In the public health area, epidemiologists construct models of epidemics and can identify "tipping points" -- points where the body politic begins to reverse a trend toward unhealthy behavior and reasserts healthy behaviors. Scholars such as Thomas Schelling who studied residential segregation patterns over the past generation identified points at which whole neighborhoods suddenly shifted from one racial group to another. George Galster of the Urban Institute has studied urban redevelopment efforts, both governmental and private, and has shown that those efforts often succeed only after a bad neighborhood as hit bottom, then it can rapidly be reclaimed. Jonathan Crane, a sociologist at the University of Illinois, found that when the number of role models in a community -- people with professional jobs-fell below five percent, certain indicators that had remained stable while the professional presence declined steadily from forty percent to five percent, suddenly exploded. Drop out rates doubled, the rate of child-bearing for teen age girls nearly doubled. The community infrastructure can no longer exert the same power over behavior. Two economists at the University of California at Berkley, George Kerlof and Jane Yellen have developed a complex economic model showing that community resiliency is a key ingredient in crime fighting -- that at a certain point, a community decides that crime has gotten too bad and that it should join forces with the police. The question then becomes do we have models of community resiliency as it pertains to crime -- and data to test those models? No.
At NIJ, we are thinking about the implications of the Chicago study, and this notion of community dynamics, for our own research strategy. We are moving in two directions. We are funding different methods of research -- a look at our portfolio will show a lot more ethnographic work, such as that being conducted here in New York City by Mercer Sullivan, Rick Curtis and Jeffrey Fagan. We want to bring the research process much closer to the individuals who commit crimes, and the victims, families and communities affected by crimes.
More important, long term, we are undertaking new measurement and evaluation efforts. Two of these have been publicly announced. I referred earlier to the ADAM program. If funded by Congress, we plan to have a capacity, by the year 2001, to conduct confidential interviews on a quarterly basis with randomly selected arrestees in all 75 cities over 200,000 in population (with annual surveys in rural and suburban jurisdictions), and take urine samples, to measure changes in drug use, gun use, and other criminal behaviors. This year, we expanded the ADAM research program from 23 to 35 cities. The recently released report on drug markets shows the power of the ADAM research protocol. In the six cities studies, we asked arrested drug users whether police activity had stopped them from buying drugs at least once in the year before their arrest. In Manhattan, nearly two thirds of the crack users and more than half of the heroin users said yes; in Chicago, slightly fewer than one in five said yes; and in Washington, D.C., only 2.9 percent of the crack users -- and 16.7 percent of the heroin users -- said the police had frustrated their efforts to buy drugs in the past year. If we were looking for admeasure of police effectiveness in drug enforcement at the local level, the ADAM protocol can be very useful.
Allow me to place the ADAM development in another context. Over twenty years ago, our country developed the victimization survey as a standard measure of crime -- it has been invaluable as a research and policy tool because it opened a window into the world of victimization without relying on official records. The ADAM program, although quite different in method, opens a window into the world of offending and will provide invaluable, timely data on the changing picture of crime, particularly changing drug markets.
As you may know, we have also established a Crime Mapping Research Center within NIJ. Although we are very interested in the implications of mapping for practice, we are principally interested in the research yield that comes from understanding crime in its spatial and temporal dimensions, and placing it in the context of other social developments. The Mapping Center staff are planning to inaugurate a Neighborhood Safety Sentinel Program which will model changes in those variables to enhance our ability to predict change in crime patterns at the neighborhood level.
The most ambitious new effort now under development at NIJ is called "Building Safety, Building Knowledge: Block by Block", or more affectionately by its nickname, "Block by Block." As currently envisioned, the "Block by Block" initiative would look like this. Over a five year period, NIJ would establish, at the neighborhood level, in a small number of cities, a comprehensive set of measures of community well-being -- very similar to those currently being developed by the Project on Human Development in Chicago Neighborhoods. We would include traditional measures such as crime, fear of crime, and community disorder; we would also measure public attitudes, social cohesion, offender behavior, and victim responses to crime. In essence, we are adopting the "community" as the unit of analysis for a larger research effort.
Yet, Block by Block is more than a basic research program. The working title, you will recall, is "Building Safety, Building Knowledge: Block by Block". We want also to learn about what works to prevent crime -- how to "build safety" -- and to ground our research knowledge about the impact of interventions in the community context. So, we are also planning to work closely with the leadership of the neighborhood and the larger community to test, simultaneously, a limited number of interventions that have strong foundations in the research literature and have demonstrated effectiveness. The key here is to examine the impact of these interventions by using a very diverse set of measures of impact and, as important, to examine the interactive effects of more than one intervention.
Let's be a bit more concrete. We have strong reasons to believe that mentoring programs may be effective, that police and other criminal justice interventions targeted against young people at high risk of involvement in gangs may be effective, and that conflict resolution programs may be effective. All of these programs, in different ways, are efforts to change the dynamics of the youth culture in a community and change the life course of individual young people. Is it possible that the power of each intervention will be greater if they are undertaken simultaneously? Take a second example. We have strong reasons to believe that there have been significant changes in the relationship between levels of crack cocaine and levels of violence. Yet, beyond understanding the statistical correlations between the prevalence of crack cocaine and the levels of homicide, we have little understanding of how deliberate policy interventions might influence that relationship. Can a combination of police intervention, youth workers, and drug treatment change the attitudes and behaviors of drug users and people at risk of drug use?
In its current conception, therefore, Block by Block is both a research program and a demonstration program. We want both to measure and to test research hypotheses. Let me hasten to acknowledge the risks inherent in this venture. We are acutely aware that any effort to test more than one intervention at the same time poses risks of contamination of effects. We know that we will have difficulty -- perhaps approaching impossibility -- establishing a control or comparison community.
Yet we think these challenges are worth embracing. The poverty we face here is not a poverty of policy options -- there are abundant good ideas for what should be done to reduce crime. Rather we suffer from a poverty of research design. We have insufficient measures, over an insufficient length of time, with insufficient willingness to try more than one intervention at one time. In short, we are not presently able to conduct research in a way that reflects the complexity -- and the potential power -- of real life and real communities.
Compare our relative ignorance about changing crime conditions to the number of measures and indicators we have about changing economic conditions. We know about housing starts, savings rates, rises in consumer price index, purchases of durable goods -- in short, we have a multifaceted set of early warning systems that allow us to forecast changes in broader markets. With this information, we can take corrective measures, and only take those measures that are appropriate to the circumstance. We have no similar capability to anticipate changes in the crime conditions facing our country, and one result is that we waste valuable public resources and governmental authority swatting at crime problems that do not exist. The experience in Boston has shown that a very targeted, highly concentrated expenditure of enforcement power, directed at a carefully diagnosed crime problem, grounded in solid research theory about deterrence of criminal behavior, has virtually ended juvenile handgun homicides. Boston practitioners will tell all who listen that the key ingredient in their success was the development, by the Kennedy School, of solid research on the overlapping problems of guns, gangs and juvenile offending, research that formed the basis for Boston's strategic interventions.
This is not an argument to abandon the medical model of evaluation research. On the contrary, I believe strongly we need to geometrically increase our investment in testing research hypotheses using the most rigorous research designs that can be implemented in real world settings. Nor is this the occasion for a full critique of the medical model. Yet, I note with great interest that one of our staunchest advocates for the model of medical trials in crime prevention research -- Prof. Lawrence Sherman -- publicly announced a shift in his position last month in a talk at the Police Foundation.
"For years, Sherman (1984, 1992) and others have used medicine as the exemplar of a profession based upon strong scientific evidence. Sherman has praised medicine as a field in which practitioners have advanced training in the scientific method, which they use to keep up to date with the most recent research evidence by reading medical journals. He has cited the large body of randomized controlled experiments in medicine -- now estimated to number almost one million in print (Sackett and Rosenberg, 1995) -- as the highly rigorous scientific evidence used to guide medical practices. He has suggested that policing should therefore be more like medicine.
Sherman was wrong. Like so many conclusions, this one was reached on the basis of inadequate evidence. Better data on how doctors work reveals medicine to be a battleground between research and practice. The idea that most practice should be based on research has spawned a sweeping new strategy called "evidence-based medicine," "widely hailed as the long-sought link between research and practice" (Zuger, 1997)." 
He went on to call for evidence-based policing. I agree with him -- we should encourage methodological pluralism. We should recognize that the work of crime control and prevention does not occur in the closed systems of medical trials, but in the open systems of communities.
At NIJ -- the ADAM research program, the Crime Mapping Research Center and the Block by Block Initiative -- reflect shifts in our thinking about the research strategy necessary to capture community dynamics. Ironically, our recent experience with the rise and fall of violent crime may have provided the catalyst to our new approaches to NIJ's fundamental mission of building useful knowledge about crime and justice. Yet this is certainly not our mission alone. The development of useful knowledge about crime and justice is equally the task of researchers, police officials, policy makers, community leaders -- and I welcome your partnership in this important effort.
[note 1] Zimring, Franklin & Gordon Hawkins. 1997. "Lethal Violence and the Overreach of American Imprisonment." NIJ Research Report. Washington DC: US Department of Justice.
[note 2] Bureau of Justice Statistics. National Crime Victimization Survey. Washington, D.C.: U.S. Department of Justice.
[note 3]New York Police Department. 1997. Preliminary Homicide Report. New York.
[note 4] Lattimore, Pamela K., James Trudeau, K. Jack Riley, Jordan Leiter, and Steve Edwards. 1997. "Homicide in Eight U.S. Cities: Trends, Context, and Policy Implications." NIJ Research Report. Washington DC: US Department of Justice
[note 5] Age-Specific Arrest Rates and Race-Specific Arrest Rates for Selected Offenses.1965-1992. Uniform Crime Reporting Program, Federal Bureau of Investigation, Washington, DC: U.S. Department of Justice.
[note 6] Supplementary Homicide Report. 1965-1992. Uniform Crime Reporting Program, Federal Bureau of Investigation, Washington, DC: U.S. Department of Justice.
[note 7] Blumstein, Alfred. 1995. "Violence by Young People: Why the Deadly Nexus?" National Institute of Justice Journal. Washington DC: U.S. Department of Justice.
[note 8] Blumstein, Alfred. 1995. "Violence by Young People: Why the Deadly Nexus?" National Institute of Justice Journal. Washington DC: U.S. Department of Justice
[note 9] Golub, Andrew & Bruce Johnson. 1997. "Crack's Decline: Some Surprises Across U.S. Cities." National Institute of Justice Research in Brief. Washington DC: US Department of Justice
[note 10] Golub, Andrew & Bruce Johnson. 1997. "Crack's Decline: Some Surprises Across U.S. Cities." National Institute of Justice Research in Brief. Washington DC: US Department of Justice
[note 11] Lattimore, Pamela K., James Trudeau, K. Jack Riley, Jordan Leiter, and Steve Edwards. 1997. "Homicide in Eight U.S. Cities: Trends, Context, and Policy Implications." NIJ Research Report. Washington DC: US Department of Justice
[note 12] Riley, Jack K. 1998. "Crack, Powder Cocaine, and Heroin: Drug Purchase and Use Patterns in Six U.S. Cities." National Institute of Justice Research Report. Washington DC: US Department of Justice
[note 13] Earls, Felton J. & Christy A. Visher. 1997. "Project on Human Development in Chicago Neighborhoods: A Research Update." National Institute Research In Brief. Washington, D.C.: U.S. Department of Justice
[note 14] Sampson, Robert & Stephen Raudenbush & Felton Earls. 1997. "Neighborhoods and Violent Crime: A Multilevel Study of Collective Efficacy." Science, Vol.277. American Association for the Advancement of Science.
[note 15] Butterfield, Fox. "Study Links Rate of Violence to Cohesion in Community." New York Times. August 17, 1997.
[note 16] Kelling, George. "Crime Control, the Police, and the Cultural Wars: Broken Windows and Cultural Pluralism." December 2, 1997. National Institute of Justice Perspectives on Crime and Justice Lecture Series. Washington, DC
[note 17] Gladwell, Malcolm. "The Tipping Point." June 3, 1996. The New Yorker.
[note 18] Bennett, Amanda. "Economists Demonstrate That Neighbors, Not Wardens, Hold Keys to Cutting Crime." December 7, 1994. Wall Street Journal.
[note 19] Fagan, Jeffrey. 1998. "Adolescent Violence: A View From the Street." National Institute of Justice Research Preview. Washington, DC: U.S. Department of Justice
[note 20] Sherman, Lawrence W. "Evidence-Based Policing." February 18, 1998. Police Foundation Second Invitational Lecture on Ideas in Policing. Washington, DC.