The researchers conducted this study to provide
evidence of the effectiveness of alternative drug enforcement
strategies. There was particular interest in examining the relative
effectiveness of strategies drawn from professional- versus
community-oriented models of policing. The professional model
emphasizes police responsibility for crime control, whereas the
community model stresses the importance of a police-citizen
partnership in crime control.
The cities of Oakland, California, and Birmingham,
Alabama, were chosen for the experiment based on similarity of
population size, demographics, number of police officers, and history
of drug problems. In each city, the main focus was on evaluating the
impact of alternative policing methods on citizens' attitudes and
reported crime. The researchers selected beats to either receive an
experimental treatment or to act as a control group. The treatments
consisted of either increasing enforcement activities based on the
professional policing model, or increasing police-citizen cooperation
based on the community policing model. In Oakland, the enforcement
activities were conducted by Special Duty Unit 3 (SDU-3) and consisted
of undercover buy-bust operations, aggressive patrols, and motor
vehicle stops. The community policing activity consisted of
door-to-door contacts with citizens. The Oakland data contain
information on four beats: one control and three treatments. For the
period May-October 1988, SDU-3 operated in Beat 25, community policing
was practiced in Beat 7, both SDU-3 and community policing were in
effect in Beat 34, and Beat 11 served as the control group, with no
change in police activities. One rotation of treatments occurred among
the beats during the period November 1988-April 1989. During that
time, SDU-3 operated in Beat 34, community policing was practiced in
Beat 11, both treatments were in effect in Beat 7, and Beat 25 served
as the control group. In Birmingham, the enforcement activities
included less visible buy-busts and sting operations conducted by the
narcotics unit. The community policing efforts involved door-to-door
contacts, as in Oakland, and the establishment of a police substation.
In contrast to the Oakland site, a control group did not exist in
Birmingham. Three beats received three different treatments: Beat 61
used narcotics unit enforcement, Beat 84 practiced door-to-door
policing, and Beat 62 had a police substation. No rotation of
treatments occurred. These treatments were in effect from September
1988 to February 1989. Structured observations of the police were
performed in Oakland.
A random sample was used to select respondents for Wave I
of the panel surveys. This resulted in 787 and 580 respondents in
Oakland and Birmingham, respectively. Wave II panel members were the
Wave I respondents reduced by attrition. Wave II respondents totaled
506 and 438 for Oakland and Birmingham, respectively. Police patrols
were selected for observation on a judgmental basis. In Oakland, 82
out of 220 (37 percent) Special Duty Unit 3 tours were observed. The
crime data cover reported crime during the periods January 1987-April
1989 and January 1987-September 1989 for Oakland and Birmingham,
respectively.
For the panel surveys, the universe consisted of
residents, 18 years and older, residing in the target beats. In
Oakland, the sample of structured observations was drawn from a
universe of Special Duty Unit 3 patrols conducted during the treatment
period.
The researchers collected data from surveys of
residents, structured observations by trained observers, and crime
reports. The units of analysis are, respectively, individuals,
interactions between police and citizens, and reported incidents of
crime.
structured observations, personal interviews, and crime
reports
survey data, and event/transaction data
experimental data
Each data source focused on collecting specific
types of information. Panel surveys in both Oakland and Birmingham
asked questions on topics such as awareness of drug trafficking
problems, prevalence of crime other than drug trafficking, awareness
of specific police programs aimed at controlling crime and drugs,
perceived safety of the neighborhood, quality of life in the
neighborhood, and satisfaction with police service. The structured
observations in Oakland assessed the major roles, behavior, and
decisions of police and citizens in drug-related encounters.
Observational data were recorded using two different instruments: a
"long form" used in 353 encounters in which an arrest was made, and a
"short form" used in 130 encounters in which police briefly stopped
and questioned individuals but did not make an arrest. (Structured
observations were not conducted in Birmingham.) Drug arrest data were
gathered for both cities. Location of arrest, crime type, suspect
information, and evidence were of particular interest. Additional
crime data were collected covering offenses against persons (homicide,
rape, and felonious assault), burglaries, and robberies.
Response rates for Wave I of the panel surveys
were 58 percent and 84 percent in Oakland and Birmingham,
respectively. In Oakland, Wave I consisted of 787 respondents.
Sixty-four percent of those interviewed in Wave I were
reinterviewed in Wave II. In Birmingham, Wave I consisted of 580
respondents. Seventy-six percent of those individuals were
reinterviewed for Wave II. In Oakland, structured observations were
conducted in 82 out of 220 (37 percent) Special Duty Unit 3
tours. This resulted in 483 observations.
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