Although Cahill and colleagues (2008) reported significant decreases in the number of calls reporting shots fired and in gang-related incidents in the target area, no significant differences were found for calls to report vandalism, serious violence incidents, and gang-related serious violence incidents. In addition, for measures of crime, the findings below suggest the Community Law Enforcement and Recovery Program (CLEAR) did not displace gang crime into the surrounding area. Furthermore, changes in the education outcomes cannot be correlated to the Los Angeles Gang Reduction Program (LA GRP)’s prevention and intervention services, as no significance levels were reported.
Calls, Shots Fired
A significant decrease of 8.23 calls per month to report shots fired was observed in the target area starting February 2004. Conversely, there were no significant differences in the comparison and displacement areas, although they both noted decreases in calls per month: 1.79 calls starting December 2003, and 0.90 calls starting February 2004, respectively.
There were no significant differences in the number of calls per month to report vandalism in any of the study areas. A slight increase in calls per month was observed in the target area (0.62 starting January 2004) and comparison area (0.55 starting February 2004), while a small decrease was observed in the displacement area (0.25 starting November 2003).
Incidents, Serious Violence
There were no significant differences in the number of incidents per month of serious violence in any of the study areas. Both the target and comparison areas saw nonsignificant decreases in incidents. The target area saw a decrease of 12.65 incidents per month starting October 2003. The comparison area saw a decrease of 6.42 incidents per month also starting October 2003. The displacement area saw a nonsignificant increase of 3.36 incidents per month starting February 2004.
The target area saw a significant decrease of 6.78 gang-related incidents per month starting February 2004, while the comparison area saw a nonsignificant decrease of 2.91 incidents per month starting November 2003. Alternatively the displacement area saw a nonsignificant increase of 2.28 incidents per month starting January 2004.
Incidents, Gang-Related Serious Violence
Although nonsignificant decreases in the number of gang-related serious violence incidents were reported in the target and displacement areas, researchers reported a significant decrease in similar incidents in the comparison area. The target area had a decrease of 8.71 incidents per month starting December 2003, and the displacement area had a decrease of 1.76 incidents per month starting September 2003. However, starting September 2003, the comparison area saw a significant decrease of 5.37 incidents per month. Based on the evidence reported, it is unknown if CLEAR had a direct effect on gang-related serious violence incidents.
Attendance levels for the target and comparison elementary, middle, and high schools remained unchanged over the study period.
Decreased Disruptive Behavior Resulting in Disciplinary Action
Due to the small number of students served, the short intervention period, and the data reported, it is unclear if LA GRP services had a direct effect on this outcome. Although very small changes were noted by researchers, suspension rates of the elementary schools remained stable between the 2002–2003 and 2006–2007 school years. There were no expulsion referrals for any of the elementary schools in either school year. The suspension rate (per 100 students) at Stevenson Middle School (target school) in the 2002–2003 school year (25.68) was 62.4 percent lower than that of Belvedere Middle School (comparison school) during the same time (41.13). But by 2006–2007, Stevenson’s suspension rate of 26.28 was almost twice that of Belvedere’s rate of 16.13. Both middle schools experienced a change in expulsion referrals. Stevenson’s referrals decreased from 1 to 0, while Belvedere’s referrals decreased from 5 to 2.
The target area high school, Roosevelt High School, saw a greater decline in suspensions than the comparison high school, Garfield High School. Roosevelt’s suspension rate dropped from 23.23 in the 2002–2003 school year to 14.31 in the 2006–2007 school year, while Garfield’s rate only dropped from 17.71 to 12.37. Conversely, both high schools experienced an increase in expulsion referrals. Roosevelt saw an increase of referrals from 1 in the 2002–2003 school year to 6 in the 2006–2007 school year. During the same time periods, Garfield’s referrals increased from 5 to 10.
Cahill and colleagues (2008) used a quasi-experimental design to analyze the preliminary impact of the Office of Juvenile Justice and Delinquency Prevention’s Gang Reduction Program (GRP) on gang-related crime in Los Angeles (LA), California.
The study areas included:
- The target area, a 2-square-mile section of the southeasternmost corner of Boyles Heights in East LA, with 25,441 residents. The target area was 97 percent Hispanic and 50 percent male. Thirty-two percent lived below the poverty level.
- The comparison area, a section northwest of the target area, with 24,454 residents. This area was selected for its similar crime rates and demographic characteristics to the target area. The comparison area was 89 percent Hispanic and 52 percent male. Thirty-six percent lived below the poverty level.
- The displacement areas, including the section adjacent to the northern edge of the target area, with 18,073 residents, chosen because of its socioeconomic similarity to the target area, and a section west of the target area, chosen because of its vulnerability to crime. The displacement areas were 94 percent Hispanic and 49 percent male. Thirty-one percent lived below the poverty level.
With assistance from the Los Angeles Police Department Information Technology Department (LAPD–ITD), researchers obtained reported crime incidents, arrests, and calls-for-service records for all offense types in order to assess the impact of the Community Law Enforcement and Recovery Program (CLEAR) on crime in the target area. Researchers audited the LAPD Hollenbeck Gang Unit’s incident files in order to include a comprehensive record of gang incidents. Measures included calls for shots fired, calls for vandalism, serious violence incidents, gang-related incidents, and gang-related serious violence incidents. The number of gang-related incidents is the most direct measure of effectiveness for CLEAR. A time-series analysis was used to assess changes in volume and seriousness of criminal activity in each study area. Monthly time series were created for each study area from January 2002 through December 2006. Researchers considered intervention points from September 2003 through February 2004.
The researchers also examined education outcomes to assess the success of the LA GRP’s prevention and intervention services in academic achievement, increased attendance, and decreased disruptive behavior resulting in disciplinary action. Academic records were not collected for participants, thus academic achievement could not be measured. School-level data were collected for four schools in the target area (Dena Elementary School, Sunrise Elementary School, Stevenson Middle School, and Roosevelt High School) and three schools outside of the target area (Hammel Elementary School, Belvedere Middle School, and Garfield High School), which served as control schools. Control schools were not from the comparison area but were selected because of similarities in total enrollment, racial composition, percentage of students eligible for the Free/Reduced Lunch program, and percentage of students who were English learners. Data were collected from the official Web site of the Los Angeles School District for 1 year prior to LA GRP implementation (2002–2003) and 1 year after implementation (2006–2007).
Researchers expected to collect outcome information on the domains of community, corrections, crime, education, and health; however, they were not able to obtain measures in community, corrections, and health.
The Office of Juvenile Justice and Delinquency Prevention's Gang Reduction Program was a $10 million, multisite, multiyear initiative. The Los Angeles, California, site received an award of $2.5 million for a 3-year period.